Tiago Cacao defeated Yannick Mertens 6-3 4-6 6-4 in the Portugal F1 semi-final on hard. The upset overturned the form book — Yannick Mertens came in leading the head-to-head 2–0, but Tiago Cacao had been the form player, winning 8 of their last 10 on hard. Tiago Cacao claimed a first win over Yannick Mertens in three meetings, narrowing the head-to-head to 2–1.
| Date | Tournament | Round | Surface | Winner | Score |
|---|---|---|---|---|---|
| 2019-08-23 | M15 Sintra 2 | QF | hard | Yannick Mertens | 6-3 6-7(8) 7-6(1) |
| 2016-09-26 | Portugal F11 | QF | hard | Yannick Mertens | 6-3 7-6(4) |
Averages over each player's completed matches in the selected window (40 vs 40). 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