Greek sixth seed Stefanos Tsitsipas comfortably beat German world number 110 Maximilian Marterer to reach the second round of the French Open.

The Australian Open semi-finalist won 6-2 6-2 7-6 (7-4) to set up a second-round meeting with Bolivian world number 92 Hugo Dellien.

Nicolas Mahut, 37, produced an upset, coming from two sets down to beat 16th seed Marco Cecchinato of Italy.

The French wildcard beat the 2018 semi-finalist 2-6 6-7 (6-8) 6-4 6-2 6-4.

Elsewhere, Japanese seventh seed Kei Nishikori beat French world number 153 Quentin Halys 6-2 6-3 6-4.

The two-time Roland Garros quarter-finalist will face Frenchman Jo-Wilfried Tsonga or German Peter Gojowczyk in the second round.

Croatian 11th seed Marin Cilic is also through with a 6-3 7-5 6-1 victory over Italian Thomas Fabbiano.

The former US Open champion will face Bulgarian world number 47 Grigor Dimitrov, who beat Serb Janko Tipsarevic, in the second round.

Tsitsipas has been in good form heading into Roland Garros, reaching the final of the Madrid Open following victories over fourth seed Alexander Zverev and five-time champion Rafael Nadal.

He also captured his third ATP title - and his first on clay - when he beat Uruguay's Pablo Cuevas 6-3 7-6 (7-4) to win the Estoril Open before losing in the semi-finals to Nadal in Rome.

The Greek, who is the rising star on the ATP Tour, also played in clay tournaments in Monte Carlo and Barcelona - winning 13 matches in total on clay before coming to Paris.

"It is quite different to other tournaments I have played. It is slow. It is not too fast, it is fine. I love playing on this court though. It gives you another energy on the big arenas," said Tsitsipas following his win over Marterer.

"These are the moments that we are practising and dreaming of."