London - Czech veteran Barbora Strycova, who is pondering retirement, marched into the quarter-finals at Wimbledon on Monday beating 21st seed Belgian Elise Mertens 4-6, 7-5, 6-2.
It is the second time the unseeded 33-year-old, who beat fourth-seeded Kiki Bertens in the previous round, has reached the quarter-final stage, the previous occasion in 2014.
Strycova will play either compatriot and two-time Wimbledon champion Petra Kvitova or Britain's French Open semi-finalist Johanna Konta in Tuesday's quarter-finals.
Wimbledon results on Monday (x denotes seeding):
Men
4th round
Roberto Bautista Agut (ESP x23) bt Benoit Paire (FRA x28) 6-3, 7-5, 6-2
Rafael Nadal (ESP x3) bt Joao Sousa (POR) 6-2, 6-2, 6-2
Women
4th round
Alison Riske (USA) bt Ashleigh Barty (AUS x1) 3-6, 6-2, 6-3
Serena Williams (USA x11) bt Carla Suarez Navarro (ESP x30) 6-2, 6-2
Barbora Strycova (CZE) bt Elise Mertens (BEL x21) 4-6, 7-5, 6-2
Elina Svitolina (UKR x8) bt Petra Martic (CRO x24) 6-4, 6-2
Simona Halep (ROU x7) bt Cori Gauff (USA) 6-3, 6-3
Zhang Shuai (CHN) bt Dayana Yastremska (UKR) 6-4, 1-6, 6-2