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Kalshi / Polymarket / ProphetX

Marcos Giron vs. Valentin Royer

ATP·2026-08-23

Best price · tap to trade

Marcos Giron51¢1.96x

Valentin Royer49¢2.04x

About This Market

Traders give Marcos Giron about a 51.4% chance. Valentin Royer follows at 49.8%. Compare prices from Kalshi, Polymarket, and ProphetX. The largest cross-platform price difference is 3.5 percentage points.

Marcos Giron vs. Valentin Royer — ATP Tennis match scheduled for 2026-08-23. Compare live prediction market odds from Kalshi, Polymarket, and more on Prediction Hunt.

Learn more:How to Read Prediction Market Prices Compare Fees Before You Trade New to Polymarket?

Live Markets

3 platforms

Moneyline

OutcomeConsensus

Kalshi

Polymarket

ProphetX

Best price

Marcos GironARB

51%

51¢

54¢

1.96x51¢

Platform	Implied %	Yes bid / ask		No bid / ask
Kalshi	50.5%	50¢	51¢	49¢	50¢
Polymarket	50.0%	50¢	51¢	49¢	50¢
ProphetX	53.5%	54¢	54¢	50¢	50¢

Valentin RoyerARB

50%

49¢

50¢

2.04x49¢

Platform	Implied %	Yes bid / ask		No bid / ask
Kalshi	49.0%	48¢	49¢	51¢	52¢
Polymarket	50.0%	49¢	50¢	50¢	51¢
ProphetX	50.3%	50¢	50¢	54¢	54¢

Kalshi

Polymarket

ProphetX

Market RulebooksOfficial settlement criteria and edge cases

Official settlement criteria, resolution sources, and edge cases across Kalshi and Polymarket and ProphetX.

Rules for Candidate:

Kalshi

Primary Rule

If Valentin Royer wins the Royer vs Giron professional tennis match in the 2026 ATP Winston Salem Round Of 64 after a ball has been played, then the market resolves to Yes.

Edge Cases

The following market refers to the Royer vs Giron professional tennis match in the 2026 ATP Winston Salem Round Of 64 after a ball has been played. If the match does not occur (signaled by a ball being played) due to a player injury, walkover, forfeiture, or any other cancellation (all before the match starts), the market will resolve to a fair price in accordance with the rules. If this match is postponed or delayed, the market will remain open and close after the rescheduled match has finished (within two weeks). Kalshi is not affiliated, associated, authorized, endorsed by, or in any way officially connected with the Governing League. All trademarks, logos, and brand names are the property of their respective owners.

Resolution Oracles

Kalshi Rules

Polymarket

Primary Rule

This market refers to the tennis match between Valentin Royer and Marcos Giron in the Winston-Salem Open, originally scheduled for August 24, 2026 at 10:00AM ET. This market will resolve to 'Valentin Royer' if Valentin Royer advances against Marcos Giron. This market will resolve to 'Marcos Giron' if Marcos Giron advances against Valentin Royer. If the match is canceled (not played at all), ends in a tie, or a winner has not been determined by September 7, 2026, 11:59 PM ET (14 days after the scheduled start), this market will resolve to 50-50. If the match begins but is not completed, and one player advances due to the opponent's retirement, default, or disqualification, this market will resolve to the player who advances. If the match ends in a walkover (player withdraws before the start and the other advances automatically), this market will resolve to 50-50. The primary resolution source will be official information from the ATP Tour. A consensus of credible reporting may also be used.

Resolution Oracles

UMA Optimistic OracleConsensus of Sources

ProphetX

Primary Rule

Sports moneyline - resolves based on official game outcome per ProphetX Prediction Rules

Resolution Oracles

ProphetX Rules

Frequently Asked Questions

What does the Marcos Giron vs. Valentin Royer prediction market track?

The outcomes listed above show how traders are pricing this question. Compare outcome prices from Kalshi, Polymarket, ProphetX in one place. Each price reflects the market’s implied probability, not a guaranteed result.

What are the latest Marcos Giron vs. Valentin Royer odds?

The latest available prices are Marcos Giron: 50.5¢ on Kalshi, 50.0¢ on Polymarket, 53.5¢ on ProphetX; Valentin Royer: 49.0¢ on Kalshi, 50.0¢ on Polymarket, 50.3¢ on ProphetX. Prices are quoted in cents per $1 share. Check the venue for executable prices and available liquidity.

Why do Marcos Giron vs. Valentin Royer odds vary across prediction markets?

The largest price difference shown across venues is 3.5 percentage points. Venues have different traders, liquidity and fees, so their prices can differ. A price gap alone does not establish an executable arbitrage opportunity; compare settlement rules and the actual buy and sell prices.

How do Marcos Giron vs. Valentin Royer prediction market payouts work?

For example, Marcos Giron at 51.4¢ implies about a 51.4% chance. For a standard $1 contract, a share pays $1 if its outcome settles as correct and $0 if it settles as incorrect. A winning share bought at 40¢ earns 60¢ before fees. Check each venue’s settlement rules, fees and eligibility before trading.

Marcos Giron vs. Valentin Royer

About This Market

Marcos Giron vs. Valentin Royer

About This Market

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Frequently Asked Questions

Marcos Giron vs. Valentin Royer

About This Market

Marcos Giron vs. Valentin Royer

About This Market

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Arkansas-Pine Bluff Golden Lions vs. Southern Jaguars

Varvara Lepchenko vs. Aliaksandra Sasnovich

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Price History

Live Markets

Moneyline

Smart Trade Router

Resolution Oracles

Market Rulebook: Marcos Giron vs. Valentin Royer

Frequently Asked Questions