German sixth seed Alexander Zverev blew hot and cold with his serve but had enough artillery to take down Russian qualifier Roman Safiullin 7-6(4) 6-3 7-6(1) to reach the third round of the French Open on Wednesday. Zverev and Safiullin never contested a Tour-level match before Wednesday but met three times as juniors with the German winning all three in straight sets. But the 182nd-ranked Russian, who mostly plies his trade on the challenger circuit, went toe-to-toe with Zverev in the baseline battle in the opening set before the German got the crucial break in the 11th game. Serving for the set, Zverev committed two double-faults to give away the advantage and had another in the tie-breaker but he recovered to take the lead with back-to-back aces in the first match of the day on Suzanne Lenglencourt. "First week you play against guys, some of them play first, second, third time of a Grand Slam," Zverev told reporters. "They"re very motivated. They"re excited to play on the big courts, like I thought today. "I think he played a fantastic match. I"m happy to be through in three sets. The match definitely wasn"t easy." Double faults continued to haunt the 24-year-old German in the second set as he smashed his racquet on the court in frustration and suffered a service break. But he recovered spectacularly to take the set by winning five games in a row. Safiullin continued to trouble Zverev in the third set and forced the German, who rallied from two sets down to defeat qualifier Oscar Otte in Sunday"s opening round, to dig deep. Zverev, who served 15 aces against 10 double faults, was once again forced to overcome a 4-1 deficit to take the third set into a tiebreaker. But the U.S. Open finalist served strongly and outplayed Safiullin in the tiebreaker to set up a clash against Serbia"s Laslo Djere, who came back from a two-set deficit to beat countryman Miomir Kecmanovic 4-6 4-6 6-3 6-2 6-3. "Today, especially last two sets, they could have gone both ways, especially the third. The second I thought I was in control more," said Zverev, who is considered one of the title contenders at Roland Garros this time after his win in Madrid. "But, yeah, I"m happy to be through in three sets. I"m happy not to have played another five-setter. I think it"s going to be important for me during the course of this tournament."