Bastad (250) - Predicted accuracy 88.9% !

TenELOs uses the Surface Elo (Clay) ratings—not a generic overall Elo—to determine the predicted winner for each match. (TenELOs)

Using those pre-match Clay Elo ratings, the Nordea Open (Båstad) 2026 tournament produced:

• 24 correct predictions out of 27 matches
• 88.9% accuracy
• All 4 quarterfinals predicted correctly
• Both semifinals predicted correctly
• Final predicted correctly

That is an exceptionally strong tournament-level performance for an Elo-based model.

Why Surface Elo matters

Båstad is played on outdoor clay, where specialists often outperform their ATP ranking. Surface-specific Elo captures this by rating players separately on clay, hard and grass, which is one reason it can outperform ranking-based predictions.

Is 24/27 elite?

Yes.

For comparison:

• 70–75% is a strong long-term prediction rate for ATP match models.
• 88.9% over a full ATP 250 tournament is outstanding.
• Getting every QF, SF and the final correct is especially impressive because those rounds usually contain closer matchups between similarly rated players.

The real test is whether TenELOs can maintain that level over many tournaments. However, if it continues producing documented performances like the Nordea Open, Mallorca, and Wimbledon examples shown on its site, it would compare very favorably with other publicly available Elo-based tennis prediction systems. (TenELOs)