Will Stefanos Tsitsipas win the 2026 Men's US Open?
No meaningful repricing — the probability is steady.
The pricing is supported by healthy trading volume and market depth, a tight spread.
How credible was the move?
Three separate questions — a move can be genuine while the latest price is still settling. Methodology →
Move validity
Is the move backed by real trading and depth?
StrongThe pricing is supported by healthy trading volume and market depth, a tight spread.
Consensus stability
Has the market settled at the new probability?
StableThe probability has held near its current level over the past several hours.
Contract clarity
Will the rules resolve without ambiguity?
HighThe resolution rules are relatively specific, with a named source and a defined deadline.
From the latest trade tape (most recent 200 prints) — a live activity sample, not a lifetime total.
What this market actually measures
The 2026 U.S. Open tennis tournament is scheduled for August 23 - September 13, 2026.
This summary shows the opening of the venue's official rules. ProbCast has not yet generated an independent plain-English interpretation for this contract — review the full rules before relying on it.
View full official resolution rules
The 2026 U.S. Open tennis tournament is scheduled for August 23 - September 13, 2026. This market will resolve to the player that wins the 2026 U.S. Open Men’s Singles Tournament. If at any point it becomes impossible for a listed player to win the 2026 U.S. Open Men’s Singles Tournament per the rules of the tournament, the corresponding market will resolve to “No”. If the 2026 U.S. Open Men’s Singles Tournament is cancelled, postponed after October 31, 2026, or there is otherwise no winner declared within that timeframe, this market will resolve to “Other”. The primary resolution source will be official information from the U.S. Open (https://www.usopen.org/index.html); however, a consensus of credible reporting may also be used.
What could move this market next?
- The scheduled event takes placeSeptember 12, 2026 at 8:00 PM ET
The contract resolves on the event's outcome.
Derived from the contract's own mechanics as of Sep 5, 2:48 AM ET. ProbCast does not list scheduled meetings, announcements, or data releases it cannot verify.
Advanced analysis (experimental)
Research signals — these models are still accumulating the history needed for full validation, and they can disagree with the headline read. Model confidence: high · expected error ±9 pts.
What's happening
A tight, deep, quote-driven book with little executed flow. The price is stable but reflects resting quotes more than active trading.
- Tight spread on a liquid, calm market
The latest price is a usable but caveated read — weigh it with the market state.
More details — reliability score, dynamics, durability
- Stable consensus96%
- Choppy / mean-reverting2%
- News repricing1%
Short-term motion of the price line (~1h), distinct from the environment above — not a prediction of the final outcome.
Secondary read: leaning toward Trading normally.
A read-only classification of the market environment — how much weight the current price deserves as a read of consensus. It describes conditions, never a trade.
Market data
24h volume
$85K
Liquidity
$112.3K
Total volume
$261.8K
- Category
- Macro / Fed
- Venue
- Polymarket
- Open interest
- —
- Spread
- 0.1 pts
- Best bid
- 0.9%
- Best ask
- 1.0%
- 7-day range
- 0.8% – 0.9%
- Resolves
- Sep 12, 2026