Dominic Thiem saved two match points to defeat Roger Federer 3-6, 7-6 (13/11), 6-4 and reach the Madrid Open semifinals on Friday. Austrian fifth seed and Barcelona champion Thiem will on Saturday play world number one Novak Djokovic who advanced on a walkover when opponent Marin Cilic withdrew with a stomach virus. Federer, playing his first clay court event in three years, squandered two match points in the 15-minute second set tiebreak before Thiem levelled the tie on a sixth set point. Meanwhile, Simona Halep closed in on a return to the top of the world rankings after beating Belinda Bencic 6-2, 6-7 (2/7), 6-0 to advance to the women’s final. Halep, currently No. 3 in the world, will reclaim the number one ranking should she win her third title at the Caja Magica. Bencic had defeated Halep in their last two matches, but the reigning French Open champion, who lifted the trophy in Madrid in 2016 and 2017, came through in just under two hours. World number one and two-time Madrid champion Djokovic, meanwhile, walked into the semifinals when ninth seed Marin Cilic withdrew before their match with stomach problems. “I am sorry to announce that I must withdraw from today’s match. I have had a terrible night dealing with a case of food poisoning,” wrote Cilic in a statement. “I am extremely disappointed to have my time in Madrid end in this way. Thank you for the support.” Halep awaits either Dutch seventh seed Kiki Bertens, a finalist in Madrid last year, or 2017 US Open champion Sloane Stephens. “It’s such a nice feeling to be back in the final here. I really enjoy playing in Madrid, it motivates me,” Halep said. The third seed comfortably claimed the opening set but let her game lapse slightly in the second. Bencic, who opened the door for Halep to possibly return to the top of the world ranking with her quarter-final defeat of current No. 1 Naomi Osaka, took the tight second set of the match in a tiebreaker. But Halep pulled herself together to blitz Bencic in the third and final set as she raced to a victory that increases her chances of returning to the top of the pile. “I was rushing too much in the second-set tiebreaker,” Halep said. “I was missing too many easy balls — I lost control of that tiebreak. “In the third, I just started over again, I played smarter, opening up the court and being more aggressive.”