London - Madison Keys was the first woman through to the women's quarter-finals at Wimbledon with a 3-6, 6-4, 6-1 win over qualifier Olga Govortsova on Monday.
The US 21st-seed was stunned by the Belarusian world number 122 in the first set on Court 18 but turned it around to win the fourth round contest in an hour and 33 minutes.
Keys faces either Polish 13th seed Agnieszka Radwanska or Serbian former world number one Jelena Jankovic - the 28th seed who knocked out defending champion Petra Kvitova in the last round - in Tuesday's quarter-finals.
Keys, 20, reached her first Grand Slam semi-final at this year's Australian Open.
Govortsova, 26, was the only qualifier to reach the last 16.