Panna Udvardy vs Elise Mertens — R16 — Monterrey Open

One return game settled the last set. Elise Mertens broke in game 8 for 5-3 behind 89 percent of first-serve points won in the decider, and she needed nothing more than that. Panna Udvardy had her openings — breaks in games 1 and 3 of the second set, the second of them for 3-0 — but she broke just twice in 13 return games to the Belgian's five, and held only 8 of her own 13. An hour and 54 minutes later, the No. 2 seed ends a two-match losing run and stands in the Monterrey quarterfinals.