Kei Nishikori chalked up his 50th career Grand Slam win on Monday when he finished his rain-delayed opening match at the French Open, resuming play with a two-set advantage gained a day earlier and completing a straight-sets win over Italy's Simone Bolelli, 6-1, 7-5, 6-3.
Starting with a 2-1 lead in the third set, Nishikori went on to grab a break and go up 5-3. He fended off two break points in the final game and served up an ace for the victory.
"It wasn't easy today ... (Bolelli) started playing a little better in the second, but still, I thought it was a great match for me," Nishikori told atpworldtour.com.
The Japanese world No. 6 faces 40th-ranked Andrey Kuznetsov of Russia in the second round of the clay-court Grand Slam event.
"I really feel confident," he said of his performance on clay in recent years, which has included capturing the title in Barcelona twice. "But on clay, I think the biggest challenge is beating Rafa and Novak and Andy, too. I think that's my next challenge."
He was referring to Rafael Nadal, Novak Djokovic and Andy Murray.
Nishikori had his best career showing at the French Open last year when he made it to the quarterfinals before falling in five sets to Jo-Wilfried Tsonga.
In the women's draw, Japan's Misaki Doi was down 6-2, 1-3 to Samantha Stosur of Australia when play was suspended until Tuesday morning due to darkness.