(Reuters) - Venus Williams suffered an upset 6-4 7-6(2) defeat at the hands of Greece’s Maria Sakkari on Friday in the quarter-final of the Silicon Valley Classic.
The 38-year-old Williams held a 3-0 lead in the opening set and was up 5-3 in the second but could not hold off a relentless opponent 15 years her junior. Williams has not advanced past the third round of a tournament since March and has yet to find the form that helped her reach two Grand Slam finals in 2017.
World No. 49 Sakkari has moved through her first three matches without dropping a set. She needed one hour and 43 minutes to beat Williams, and saved two set points in the second set in the process. Sakkari will now face American Danielle Collins who moved into the semis after former world number one Victoria Azarenka retired injured when trailing 3-0 in the second set after claiming the first in a tiebreaker.
It will be the second semi-final of the year for Collins.
Johanna Konta was also sent packing after a 7-6(4) 6-3 quarter-final loss to fourth seed Elise Mertens.
The Briton had opened the tournament with a bang on Tuesday when she shocked 23-times grand slam champion Serena Williams 6-1 6-0, the worst loss of the American great’s career.
Konta was unable to recreate the magic, however, instead squandering a 5-2 lead in the opening set against the Belgian before bowing out meekly.
Mertens, bidding for her fourth title of the year, moves into a semi-final against fifth seeded Romanian Mihaela Buzarnescu.
Writing by Jahmal Corner; Editing by Amlan Chakraborty