Boy Westerhof defeated Yannick Mertens 7-6 6-3 in the Seville CH round of 32 on clay. The upset overturned the form book — Yannick Mertens came in leading the head-to-head 2–0. Boy Westerhof claimed a first win over Yannick Mertens in three meetings, narrowing the head-to-head to 2–1.
| Date | Tournament | Round | Surface | Winner | Score |
|---|---|---|---|---|---|
| 2015-03-16 | Great Britain F4 | SF | hard | Yannick Mertens | 7-6(8) 6-0 |
| 2011-06-06 | Netherlands F1 | QF | clay | Yannick Mertens | 6-4 6-1 |
Averages over each player's completed matches in the selected window (45 vs 200). ATP, WTA & Challenger.
Each player's serve crossed against the other's return, converted to expected hold of serve. Recent completed matches, ATP, WTA & Challenger. About