London - Former Wimbledon finalist Angelique Kerber stepped up her bid to return to the title match with a 6-3, 7-6 (7/5) win against Switzerland's Belinda Bencic in the fourth round on Monday.
Kerber was beaten by Serena Williams in the 2016 final at the All England Club.
The 30-year-old German is seeded 11th and, after a week of shock defeat for her title rivals, that makes Kerber the highest ranked woman left in the draw.
Kerber, who won the Australian and US Open titles in 2016, is into her fourth Wimbledon quarter-final.
She faces Russian 14th seed Daria Kasatkina or Belgian world number 47 Alison Van Uytvanck on Tuesday.
Wimbledon results on Monday, the seventh day of the 2018 championships (x denotes seeded player):
Roger Federer (SUI x1) bt Adrian Mannarino (FRA x22) 6-0, 7-5, 6-4
Kevin Anderson (RSA x8) bt Gael Monfils (FRA) 7-6 (7/4), 7-6 (7/2), 5-7, 7-6 (7/4)
Milos Raonic (CAN x13) bt Mackenzie McDonald (USA) 6-3, 6-4, 6-7 (5/7), 6-2
John Isner (USA x9) bt Stefanos Tsitsipas (GRE x31) 6-4, 7-6 (10/8), 7-6 (7/4)
Novak Djokovic (SRB x12) bt Karen Khachanov (RUS) 6-4, 6-2, 6-2
Kei Nishikori (JPN x24) bt Ernests Gulbis (LAT) 4-6, 7-6 (7/5), 7-6 (12/10), 6-1
Rafael Nadal (ESP x2) bt Jiri Vesely (CZE) 6-3, 6-3, 6-4
Suspended due to darkness:
Juan Martin del Potro (ARG x5) leads Gilles Simon (FRA) 7-6 (7/1), 7-6 (7.5), 5-7
Dominika Cibulkova (SVK) bt Hsieh Su-Wei (TPE) 6-4, 6-1
Jelena Ostapenko (LAT x12) bt Aliaksandra Sasnovich (BLR) 7-6 (7/4), 6-0
Daria Kasatkina (RUS x14) bt Alison Van Uytvanck (BEL) 6-7 (6/8), 6-3, 6-2
Angelique Kerber (GER x11) bt Belinda Bencic (SUI) 6-3, 7-6 (7/5)
Kiki Bertens (NED x20) bt Karolina Pliskova (CZE x7) 6-3, 7-6 (7/1)
Julia Goerges (GER x13) bt Donna Vekic (CRO) 6-3, 6-2
Serena Williams (USA x25) bt Evgeniya Rodina (RUS) 6-2, 6-2
Camila Giorgi (ITA) bt Ekaterina Makarova (RUS) 6-3, 6-4