Kei Nishikori impressed in his opening assignment at the French Open on Sunday, reaching the second round after a 6-2, 6-3, 6-4 win over Frenchman Quentin Halys in just over two hours. Nishikori, the seventh seed at Roland Garros, quickly raced into a 4-0 lead after successive breaks of serve before claiming the first set while serving to love. The Japanese No 1 was just as dominant in the second set and after another two breaks, was 5-1 ahead. Halys pulled a break back for 5-3, only for Nishikori to cinch the set the very next game. In total control, Nishikori was punished for a lapse in concentration as Halys broke in the first game of the third set before moving in to a 3-1 lead. Nishikori pulled level at 3-3 but was immediately broken again. In danger of being forced to go to a fourth set, Nishikori then upped his level to win the next three games and progress to a meeting with either home favourite Jo-Wilfried Tsonga or Germany's Peter Gojowczyk. Stefanos Tsitsipas got his French Open campaign up and running in style, defeating Germany's Maximilian Marterer 6-2, 6-2, 7-5 on Sunday. Sixth seed Tsitsipas is considered one of the leading contenders at Roland Garros and the Greek star began his pursuit of a first grand slam title with a win that lasted one hour and 51 minutes. Tsitsipas was in total control for the first two sets, claiming two breaks in each as Marterer struggled to deal with the Greek's class. The third set was closer as neither player budged on serve, before Tsitsipas closed out the match in a competitive tie-break. The world No 6 will take on either India's 86th-ranked Prajnesh Gunneswaran or Bolivian world No 92 Hugo Dellien in the second round. Marin Cilic safely booked his place in the second round after a routine 6-3, 7-5, 6-1 win over Italy's Thomas Fabbiano. Cilic, who has reached the Roland Garros quarter-finals the past two years, looked instantly comfortable on the Parisian clay and was ruthless on Fabbiano's serve throughout. The Croatian was quickly a break up in the first set at 3-1, and despite surrendering his advantage at 3-3, quickly reeled off two successive breaks to clinch the opener. Cilic then found himself in danger of dropping the second set when Fabbiano broke to lead 5-4, but the 11th seed responded in style to win three straight games and take a 2-0 lead. Cilic was broken in the first game of the third set, but that was as good as it got for Fabbiano as the Croatian won the next six games to wrap up the match. Cilic will face Bulgarian Grigor Dimitrov, who defeated Janko Tipsarevic after a five-set marathon 6-3, 6-0, 3-6, 6-7, 6-4. Other results from Day 1's afternoon session include Australian Alexei Popyrin's 3-6, 6-3, 7-6, 6-3 win over Frenchman Ugo Humbert, while Norway's Casper Ruud defeated Latvia's Ernests Gulbis 6-2, 7-6, 6-0. Italian Matteo Berrettini is also through after his 6-7, 6-4, 6-4, 6-2 win against Spain's Pablo Andujar-Alba. Tunisia's Malek Jaziri was eliminated by Oscar Otte, the German claiming a 6-3, 6-1, 4-6, 6-0 victory.