TennisEdge's AI model finds no betting value in S. Costoulas vs M. Hontama (French Open on 2026-05-20) — the market is efficient, with S. Costoulas favoured at 1.40.
Independent estimates of who wins, each from a different method. The blend is what the bot prices against the market.
| Method | S. Costoulas | M. Hontama |
|---|---|---|
| Elo ratings-based, surface-weighted |
61.3% | 38.7% |
| Machine learning 29-feature gradient-boosted model |
78.3% | 21.7% |
| Serve / return point-by-point simulation |
67.9% | 32.1% |
| Blend what the bot actually prices off |
69.2% | 30.8% |
| Market implied de-vigged from the opening odds |
66.3% | 33.7% |
We publish how well these score against the closing market, including where they lose: how accurate are tennis predictions?
| Player | Surface | Elo | Record | Matches |
|---|---|---|---|---|
| S. Costoulas | hard | 1570 | 131–79 | 210 |
| M. Hontama | hard | 1597 | 153–123 | 276 |
Our own ratings, computed from match results since 2018. Players with fewer than 5 rated matches are omitted rather than shown at a provisional starting value. Last updated Aug. 4, 2026.
S. Costoulas leads 1–0 over 1 meeting. Full record.
| Date | Event | Surface | Winner | Score |
|---|---|---|---|---|
| May 20, 2026 | French Open | clay | S. Costoulas | 2 - 0 |
| L | G. Knutson | 2 - 0 | Aug. 4, 2026 |
| L | M. Inglis | 0 - 2 | July 29, 2026 |
| W | L. Cabrera | 0 - 2 | July 29, 2026 |
| L | A. Aksu | 2 - 1 | July 20, 2026 |
| W | A. Aksu | 2 - 0 | July 19, 2026 |
| L | M. Inglis | 2 - 0 | July 31, 2026 |
| W | H. Sakatsume | 2 - 0 | July 30, 2026 |
| W | J. Lu | 2 - 0 | July 29, 2026 |
| W | K. Day | 1 - 2 | July 28, 2026 |
| L | L. Tagger | 0 - 2 | July 23, 2026 |
All May 20, 2026 results & picks →
Math-only prediction: no LLM calls used