Jannik Sinner is still regaining his focus on the tennis court after his three-month doping ban .
The top-ranked player overcame a brief lapse during the first set of a 6-4, 6-2 victory over Dutch qualifier Jesper De Jong in his second match back on tour at the Italian Open on Monday.
Sinner jumped out to a 4-1 lead but then lost his serve twice as the 93rd-ranked De Jong evened the first set at 4-4.
There were poor drop shots, an inopportune double-fault and other errors from Sinner. But the Italian regained control in front of his home crowd with his powerful groundstrokes and big serve and extended his winning streak to 23 matches, dating back to October.
"I felt like I started the match very well and then I had a big drop," Sinner said. "I tried to understand what was going on. Then fortunately I broke him on 4-all again, which then gave me the confidence to continue."