Rafael Nadal rallied from a set down and fought off a match point in the third set to beat Alexander Zverev 6-7 (8), 6-0, 7-5 Wednesday and reach the quarterfinals of the BNP Paribas Open in pursuit of a fourth title. Zverev, an 18-year-old German ranked 58th in the world and in his second full year on the ATP Tour, blew a 5-2 lead in the third when he was serving for the match leading 5-3, 40-30. He made three straight forehand errors to give Nadal the break. "I am especially happy about the mentality on court, the spirit of fight during the whole match, believing that I can win a match during the whole time even in the tougher situations," Nadal said. Novak Djokovic beat Feliciano Lopez 6-3, 6-3 to stay on track for a potential semifinal against Nadal. Kei Nishikori outlasted John Isner 1-6, 7-6 (2), 7-6 (5) and next plays Nadal. "I'm actually glad to have a match like this with not much complications," said Djokovic, who was pressed in his first two wins. Djokovic will next battle seventh seeded Frenchman Jo-Wilfried Tsonga who beat Dominic Thiem 6-3, 6-2. Serena Williams beat defending champion Simona Halep 6-4, 6-3, punctuating the victory with her seventh ace. Halep has lost to Williams six of the seven times they've played and the Romanian has yet to successfully defend a title in her career. Halep had nine winners to 28 for Williams. Williams advanced to the semifinals, where she will play Agnieszka Radwanska, who defeated Petra Kvitova 6-2, 7-6 (3). Radwanska will move up to No. 2 behind Williams in next week's WTA Tour rankings based on making the semis. "It's unfortunate it can't be a final," Williams said. Nadal allowed just two points in his last two service games to escape on a day when the men's draw was dominated by younger players beating veterans. David Goffin, a 25-year-old Belgian, defeated No. 3 seed Stan Wawrinka 6-3, 5-7, 7-6 (5) and 25-year-old Canadian Milos Raonic took out No. 6 Tomas Berdych 6-4, 7-6 (7). Marin Cilic beat No. 8 Richard Gasquet 7-5, 5-7, 6-2 as temperatures reached 91 degrees (32 C) under cloudless skies in the California desert. Cilic next plays Goffin, while Raonic will play Gael Monfils, who beat Federico Delbonis 6-3, 6-4. Delbonis had upset Andy Murray in the third round. Goffin ended a 14-match skid against top-10 opponents. Zverev has lost all seven meetings against such competition. Cilic hadn't beaten a top-10 player in 1-1/2 years until he dispatched 10th-ranked Gasquet.