Top-seeded Venus Williams will play for her 50th WTA title Sunday in Stanford, in the tournament where she made her professional debut 22 years ago. Williams defeated tenacious Alison Riske 6-1, 7-6 (7/2) to reach the championship match, where she'll face third-seeded Briton Johanna Konta. Konta, ranked 18th in the world, reached her first career WTA final with a 6-4, 6-2 victory over second-seeded Slovakian Dominika Cibulkova. After sailing through the opening set, Williams had to fight her own inconsistent serve in the second. Up 5-4 in the second and serving for the match, Williams produced three double faults, wasting two match points. Two games later Williams saved two set points to force the tiebreaker, which she dominated. Williams, who won the Stanford title in 2000 and 2002, won her 49th career singles title in Taiwan in February. The 36-year-old winner of seven Grand Slam titles turned back the clock with a run to the semifinals at Wimbledon. Monfils to face Karlovic France's Gael Monfils, seeking his first ATP crown outside Europe, and Ivo Karlovic, nearing titles in consecutive weeks at age 37, advanced to the ATP and WTA Washington Open final in sweltering conditions Saturday. The 29-year-old Frenchman, whose most recent of five career titles came in 2014 at Montpellier, ripped ill German teen Alexander Zverev 6-4, 6-0 in one hour. Croatia's 35th-ranked Karlovic fired 14 aces to defeat US fifth seed Steve Johnson 6-4, 6-4 in a match where temperatures on the court reached 140 degrees Fahrenheit (60 Celsius). "There was this moment when I just wanted to lay down on the court. But I kept going," Karlovic said. "It was difficult." Belgian seventh seed Yanina Wickmayer, a 2009 US Open semifinalist, battled through the heat to oust Kazakh sixth seed Yulia Putintseva 6-4, 6-2. "It was very tough conditions out there," said Wickmayer, who seeks her fifth WTA title Sunday against America's 122nd-ranked Lauren Davis, a 6-2, 6-3 winner over 173rd-rated American Jessica Pegula. Lopez clinches Gstaad title Top-seeded Feliciano Lopez of Spain won his first career clay-court title Sunday, beating Robin Haase of the Netherlands 6-4, 7-5 in the Swiss Open final. The 34-year-old Lopez's fifth career tournament title followed two on grass and two on hard courts. Ten years after losing the Gstaad final to Richard Gasquet of France, Lopez lifted the trophy on his seventh trip back to the Swiss Alps venue. Lopez arrived ranked No. 21 and should return to the top 20 when the rankings are updated Monday. The 95th-ranked Haase had his service broken once in the first set and twice in the second as Lopez completed victory in less than 80 minutes.