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2026 U.S. Open: First Round Leader? Odds & Prediction Markets
Time left: 04d:20h:29m
Will Jon Rahm lead the 2026 U.S. Open following the first round?
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Intro
This market tracks which golfer will post the lowest cumulative score after the first round of the 2026 U.S. Open at Shinnecock Hills Golf Club. The consensus probability across Kalshi and Polymarket shows Alex Smalley at 97.0% to lead following Round 1. Resolution will be determined by the Official U.S. Open website leaderboard. Watch for the completion of Round 1 play on July 5, 2026, when the first-round leaderboard is finalized.
PredictionHero - Resolution Divergence Alerts (RDA)
Unified Resolution Criteria (Consistent across platforms)
Primary resolution logic:
Official U.S. Open website leaderboard (https://www.usopen.com/leaderboard)Core resolution logic:
- Player resolves to Yes if they finish Round 1 with the lowest cumulative score
- In case of a tie, apply tiebreaker cascade: back 9 score (lower wins), then eagles (more wins), then birdies (more wins), then bogeys (fewer wins), then alphabetical last name (earlier wins)
- Only the player with the single lowest score (or winner of tiebreaker) resolves to Yes; all others resolve to No
- If multiple players are listed as tied leaders on official source, the tiebreaker cascade determines the single Yes resolution
Edge cases & Clarifications:
- Tournament Cancellation or Postponement: If the 2026 U.S. Open at Shinnecock Hills is cancelled or postponed after July 5, 2026 11:59 PM ET, Polymarket resolves to 'Other'. Kalshi does not specify; assume void or N/A.
- No Official Round 1 Leader Declared: If no official Round 1 leader is declared by July 5, 2026 11:59 PM ET, Polymarket resolves to 'Other'. Kalshi does not specify; assume void or N/A.
- Placeholder or Unnamed Players (Polymarket): Polymarket includes placeholder markets (Player A, Player B, etc.) and an 'Other' catch-all. If the actual Round 1 leader is not one of the 100 named players, the 'Other' market resolves to Yes.
- Player Withdrawal or Disqualification: If a listed player withdraws or is disqualified before or during Round 1, they cannot be the leader. Resolution proceeds to the next-lowest score.
- Tie Persists After All Tiebreakers: If all tiebreaker criteria are exhausted and a tie remains, alphabetical last name is the final tiebreaker per Polymarket rules.
Timing:
Resolution occurs after the official completion and publication of Round 1 results on the U.S. Open website, no later than July 5, 2026 11:59 PM ET.Polymarket
This market will resolve according to the player that finishes Round 1 of the main tournament at the 2026 US Open at Shinnecock Hills Golf Club with the lowest cumulative score. In the event of a tie, this market will resolve in favor of the player with the lower score on the back 9 of the first round. If a tie still persists, this market will resolve in favor of the player that records more eagles thus far in the main tournament. If a tie still persists, this market will resolve in favor of the player who records more birdies thus far in the main tournament. If a tie still persists, this market will resolve in favor of the player who records fewer bogeys thus far in the main tournament. If a tie still persists, this market will resolve in favor of the player whose listed last name comes first alphabetically. If the 2026 US Open at Shinnecock Hills Golf Club is cancelled, postponed after July 5, 2026, 11:59 PM ET, or if an official Round 1 leader has not been declared within that timeframe, this market will resolve to "Other". The primary resolution source will be the official results published by the US Open website (https://www.usopen.com/leaderboard).
Kalshi
If Ludvig Aberg is the leader at the end of Round 1 in the 2026 U.S. Open, then the market resolves to Yes. If Daniel Berger is the leader at the end of Round 1 in the 2026 U.S. Open, then the market resolves to Yes. If Akshay Bhatia is the leader at the end of Round 1 in the 2026 U.S. Open, then the market resolves to Yes. If Keegan Bradley is the leader at the end of Round 1 in the 2026 U.S. Open, then the market resolves to Yes. If Michael Brennan is the leader at the end of Round 1 in the 2026 U.S. Open, then the market resolves to Yes. If Jacob Bridgeman is the leader at the end of Round 1 in the 2026 U.S. Open, then the market resolves to Yes. If Sam Burns is the leader at the end of Round 1 in the 2026 U.S. Open, then the market resolves to Yes. If Laurie Canter is the leader at the end of Round 1 in the 2026 U.S. Open, then the market resolves to Yes. If Patrick Cantlay is the leader at the end of Round 1 in the 2026 U.S. Open, then the market resolves to Yes. If Wyndham Clark is the leader at the end of Round 1 in the 2026 U.S. Open, then the market resolves to Yes. If Hamilton Coleman is the leader at the end of Round 1 in the 2026 U.S. Open, then the market resolves to Yes. If Corey Conners is the leader at the end of Round 1 in the 2026 U.S. Open, then the market resolves to Yes. If Pierceson Coody is the leader at the end of Round 1 in the 2026 U.S. Open, then the market resolves to Yes. If Jason Day is the leader at the end of Round 1 in the 2026 U.S. Open, then the market resolves to Yes. If Bryson DeChambeau is the leader at the end of Round 1 in the 2026 U.S. Open, then the market resolves to Yes. If Nicolas Echavarria is the leader at the end of Round 1 in the 2026 U.S. Open, then the market resolves to Yes. If Harris English is the leader at the end of Round 1 in the 2026 U.S. Open, then the market resolves to Yes. If Ethan Fang is the leader at the end of Round 1 in the 2026 U.S. Open, then the market resolves to Yes. If Alex Fitzpatrick is the leader at the end of Round 1 in the 2026 U.S. Open, then the market resolves to Yes. If Matt Fitzpatrick is the leader at the end of Round 1 in the 2026 U.S. Open, then the market resolves to Yes. If Tommy Fleetwood is the leader at the end of Round 1 in the 2026 U.S. Open, then the market resolves to Yes. If Rickie Fowler is the leader at the end of Round 1 in the 2026 U.S. Open, then the market resolves to Yes. If Ryan Fox is the leader at the end of Round 1 in the 2026 U.S. Open, then the market resolves to Yes. If Ryan Gerard is the leader at the end of Round 1 in the 2026 U.S. Open, then the market resolves to Yes. If Chris Gotterup is the leader at the end of Round 1 in the 2026 U.S. Open, then the market resolves to Yes. If Ben Griffin is the leader at the end of Round 1 in the 2026 U.S. Open, then the market resolves to Yes. If Harry Hall is the leader at the end of Round 1 in the 2026 U.S. Open, then the market resolves to Yes. If Brian Harman is the leader at the end of Round 1 in the 2026 U.S. Open, then the market resolves to Yes. If Padraig Harrington is the leader at the end of Round 1 in the 2026 U.S. Open, then the market resolves to Yes. If Tyrrell Hatton is the leader at the end of Round 1 in the 2026 U.S. Open, then the market resolves to Yes. If Russell Henley is the leader at the end of Round 1 in the 2026 U.S. Open, then the market resolves to Yes. If Lucas Herbert is the leader at the end of Round 1 in the 2026 U.S. Open, then the market resolves to Yes. If Jackson Herrington is the leader at the end of Round 1 in the 2026 U.S. Open, then the market resolves to Yes. If Ryo Hisatsune is the leader at the end of Round 1 in the 2026 U.S. Open, then the market resolves to Yes. If Nicolai Hojgaard is the leader at the end of Round 1 in the 2026 U.S. Open, then the market resolves to Yes. If Brandon Holtz is the leader at the end of Round 1 in the 2026 U.S. Open, then the market resolves to Yes. If Viktor Hovland is the leader at the end of Round 1 in the 2026 U.S. Open, then the market resolves to Yes. If Mason Howell is the leader at the end of Round 1 in the 2026 U.S. Open, then the market resolves to Yes. If Sungjae Im is the leader at the end of Round 1 in the 2026 U.S. Open, then the market resolves to Yes. If Dustin Johnson is the leader at the end of Round 1 in the 2026 U.S. Open, then the market resolves to Yes. If John Keefer is the leader at the end of Round 1 in the 2026 U.S. Open, then the market resolves to Yes. If Si Woo Kim is the leader at the end of Round 1 in the 2026 U.S. Open, then the market resolves to Yes. If Michael Kim is the leader at the end of Round 1 in the 2026 U.S. Open, then the market resolves to Yes. If Kurt Kitayama is the leader at the end of Round 1 in the 2026 U.S. Open, then the market resolves to Yes. If Jake Knapp is the leader at the end of Round 1 in the 2026 U.S. Open, then the market resolves to Yes. If Brooks Koepka is the leader at the end of Round 1 in the 2026 U.S. Open, then the market resolves to Yes. If Jackson Koivun is the leader at the end of Round 1 in the 2026 U.S. Open, then the market resolves to Yes. If Min Woo Lee is the leader at the end of Round 1 in the 2026 U.S. Open, then the market resolves to Yes. If Shane Lowry is the leader at the end of Round 1 in the 2026 U.S. Open, then the market resolves to Yes. If Robert MacIntyre is the leader at the end of Round 1 in the 2026 U.S. Open, then the market resolves to Yes. If Hideki Matsuyama is the leader at the end of Round 1 in the 2026 U.S. Open, then the market resolves to Yes. If Matthew McCarty is the leader at the end of Round 1 in the 2026 U.S. Open, then the market resolves to Yes. If Rory McIlroy is the leader at the end of Round 1 in the 2026 U.S. Open, then the market resolves to Yes. If Maverick McNealy is the leader at the end of Round 1 in the 2026 U.S. Open, then the market resolves to Yes. If Collin Morikawa is the leader at the end of Round 1 in the 2026 U.S. Open, then the market resolves to Yes. If Joaquin Niemann is the leader at the end of Round 1 in the 2026 U.S. Open, then the market resolves to Yes. If Alex Noren is the leader at the end of Round 1 in the 2026 U.S. Open, then the market resolves to Yes. If Andrew Novak is the leader at the end of Round 1 in the 2026 U.S. Open, then the market resolves to Yes. If Carlos Ortiz is the leader at the end of Round 1 in the 2026 U.S. Open, then the market resolves to Yes. If Marco Penge is the leader at the end of Round 1 in the 2026 U.S. Open, then the market resolves to Yes. If David Puig is the leader at the end of Round 1 in the 2026 U.S. Open, then the market resolves to Yes. If Mateo Pulcini is the leader at the end of Round 1 in the 2026 U.S. Open, then the market resolves to Yes. If Jon Rahm is the leader at the end of Round 1 in the 2026 U.S. Open, then the market resolves to Yes. If Aaron Rai is the leader at the end of Round 1 in the 2026 U.S. Open, then the market resolves to Yes. If Patrick Reed is the leader at the end of Round 1 in the 2026 U.S. Open, then the market resolves to Yes. If Kristoffer Reitan is the leader at the end of Round 1 in the 2026 U.S. Open, then the market resolves to Yes. If Patrick Rodgers is the leader at the end of Round 1 in the 2026 U.S. Open, then the market resolves to Yes. If Justin Rose is the leader at the end of Round 1 in the 2026 U.S. Open, then the market resolves to Yes. If Adrien Saddier is the leader at the end of Round 1 in the 2026 U.S. Open, then the market resolves to Yes. If Jayden Trey Schaper is the leader at the end of Round 1 in the 2026 U.S. Open, then the market resolves to Yes. If Xander Schauffele is the leader at the end of Round 1 in the 2026 U.S. Open, then the market resolves to Yes. If Scottie Scheffler is the leader at the end of Round 1 in the 2026 U.S. Open, then the market resolves to Yes. If Matti Schmid is the leader at the end of Round 1 in the 2026 U.S. Open, then the market resolves to Yes. If Adam Scott is the leader at the end of Round 1 in the 2026 U.S. Open, then the market resolves to Yes. If Alex Smalley is the leader at the end of Round 1 in the 2026 U.S. Open, then the market resolves to Yes. If Cameron Smith is the leader at the end of Round 1 in the 2026 U.S. Open, then the market resolves to Yes. If J.J. Spaun is the leader at the end of Round 1 in the 2026 U.S. Open, then the market resolves to Yes. If Jordan Spieth is the leader at the end of Round 1 in the 2026 U.S. Open, then the market resolves to Yes. If Sam Stevens is the leader at the end of Round 1 in the 2026 U.S. Open, then the market resolves to Yes. If Sepp Straka is the leader at the end of Round 1 in the 2026 U.S. Open, then the market resolves to Yes. If Nick Taylor is the leader at the end of Round 1 in the 2026 U.S. Open, then the market resolves to Yes. If Sahith Theegala is the leader at the end of Round 1 in the 2026 U.S. Open, then the market resolves to Yes. If Justin Thomas is the leader at the end of Round 1 in the 2026 U.S. Open, then the market resolves to Yes. If Gary Woodland is the leader at the end of Round 1 in the 2026 U.S. Open, then the market resolves to Yes. If Sudarshan Yellamaraju is the leader at the end of Round 1 in the 2026 U.S. Open, then the market resolves to Yes. If Cameron Young is the leader at the end of Round 1 in the 2026 U.S. Open, then the market resolves to Yes. If Filippo Celli is the leader at the end of Round 1 in the 2026 U.S. Open, then the market resolves to Yes. If Ugo Coussaud is the leader at the end of Round 1 in the 2026 U.S. Open, then the market resolves to Yes. If Angel Hidalgo is the leader at the end of Round 1 in the 2026 U.S. Open, then the market resolves to Yes. If Matthew Jordan is the leader at the end of Round 1 in the 2026 U.S. Open, then the market resolves to Yes. If Nathan Kimsey is the leader at the end of Round 1 in the 2026 U.S. Open, then the market resolves to Yes. If Niklas Norgaard Moller is the leader at the end of Round 1 in the 2026 U.S. Open, then the market resolves to Yes. If Rocco Repetto Taylor is the leader at the end of Round 1 in the 2026 U.S. Open, then the market resolves to Yes. If Cooper Dossey is the leader at the end of Round 1 in the 2026 U.S. Open, then the market resolves to Yes. If Adrien Dumont De Chassart is the leader at the end of Round 1 in the 2026 U.S. Open, then the market resolves to Yes. If Tom Kim is the leader at the end of Round 1 in the 2026 U.S. Open, then the market resolves to Yes. If T.K. Kim is the leader at the end of Round 1 in the 2026 U.S. Open, then the market resolves to Yes. If Graeme McDowell is the leader at the end of Round 1 in the 2026 U.S. Open, then the market resolves to Yes. If Manav Shah is the leader at the end of Round 1 in the 2026 U.S. Open, then the market resolves to Yes. If Jimmy Stanger is the leader at the end of Round 1 in the 2026 U.S. Open, then the market resolves to Yes. If Caleb Surratt is the leader at the end of Round 1 in the 2026 U.S. Open, then the market resolves to Yes. If Peter Uihlein is the leader at the end of Round 1 in the 2026 U.S. Open, then the market resolves to Yes. If Ryuichi Oiwa is the leader at the end of Round 1 in the 2026 U.S. Open, then the market resolves to Yes. If Kaito Onishi is the leader at the end of Round 1 in the 2026 U.S. Open, then the market resolves to Yes. If Taihei Sato is the leader at the end of Round 1 in the 2026 U.S. Open, then the market resolves to Yes. If Preston Stout is the leader at the end of Round 1 in the 2026 U.S. Open, then the market resolves to Yes.
Frequently asked questions
Prediction markets like those tracked here operate differently from traditional sportsbooks. Rather than a bookmaker setting fixed odds, traders on these platforms buy and sell shares representing outcomes, with prices reflecting collective belief. This crowdsourced mechanism often surfaces information faster than sportsbooks adjust their lines, especially for niche outcomes like first-round leaders. However, prediction market liquidity and sportsbook depth vary, so direct price comparisons require checking both venues simultaneously for the most current odds.
Kalshi and Polymarket can show different implied probabilities for the same outcome because of liquidity, fee structure, participant mix, and how each venue defines the contract. Each platform attracts different trader demographics, liquidity pools, and fee structures, which can create temporary price gaps on the same outcome. Kalshi and Polymarket may also have distinct user bases with varying access to golf analytics or different risk appetites. Additionally, trading volume and order-book depth differ between venues, so a large buy or sell on one platform can move its price faster than the other. These spreads typically narrow as the event date approaches and arbitrage traders exploit the differences.
This market resolves around Jul 5, 2026, once the 2026 U.S. Open first round concludes and the leaderboard is finalized. The outcome will be verified against credible public sources covering the tournament, confirming which player held the lead after 18 holes. Early resolution may occur if the round is completed before the deadline, allowing traders to settle positions promptly. Check your platform's specific terms for any tie-breaking rules or adjustments.
Major catalysts include recent PGA Tour results, injury announcements, and course-condition updates closer to June. Shifts in betting markets at sportsbooks often precede prediction market moves, as do changes in player form or withdrawal news. Weather forecasts for the U.S. Open venue can also influence expectations about scoring difficulty and which playing styles may excel. Breaking news about course setup, field changes, or standout practice-round performances typically triggers repricing across both platforms.
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