Roger beat Lorenzo in his first match on clay court Slam
Roger Federer marked his return to Roland Garros after a four-year absence with a 6-2, 6-4, 6-4 win over Italy's Lorenzo Sonego on Sunday and said he had "missed playing in Paris so much".
Federer, the 2009 champion in Paris, will face German lucky loser Oscar Otte for a place in the third round.
The 20-time major winner hadn't played the tournament since 2015 when he reached the quarter-finals.
However, on Sunday, it was as if the 37-year-old had never been away as he swept to victory in one hour 41 minutes on a rebuilt and packed Court Philippe Chatrier.
It was his 60th successive first round win at a Grand Slam.
"I missed it so much so thanks for the welcome," said Federer.
"I felt great playing on this court. It looks great and attractive, so congratulations to everyone involved.
"Hopefully I can play here again for my next match."
Federer broke serve five times and fired 36 winners past 24-year-old Sonego, the world number 73 who made the quarter-finals at the Monte Carlo Masters this year after qualifying.
"Two breaks in the first set was very important for me and when I was leading 4-0 I could take more risks, be more aggressive," said the third seed.
"I know that I can play very well on clay and I am very happy to win in straight sets."
Tsitsipas enters Round 2
Rising Greek star Stefanos Tsitsipas moved into the French Open second round on Sunday with a comfortable straight-sets win over Maximilian Marterer on Court Philippe Chatrier.
The 20-year-old sixth seed, a semi-finalist at the Australian Open earlier this year, brushed aside German Marterer 6-2, 6-2, 7-6 (7/4).
Tsitsipas raced into a 2-0 lead and edged a third-set tie-break to see off an opponent who reached the fourth round in Paris last year.
"It was a difficult first match... In the tie-break I managed to play like I did in the first two sets," said Tsitsipas, who was playing on the Roland Garros show court for the first time.
"These are the moments we're practising for and dreaming of, I'm really happy to play here."
Tsitsipas will next face either Indian Prajnesh Gunneswaran or Bolivia's Hugo Dellien as he looks to reach the third round for the first time.
New court unveiled
The new Court Simonne Mathieu, a 5,000-capacity semi-sunken arena enclosed by greenhouses, was officially unveiled on Sunday.
It forms part of the 350 million euro upgrade of the entire site which will also see the demolition of the Court 1 'bullring' after the 2018 tournament.
Spain's Garbine Muguruza, the 2016 champion, had the honour of opening proceedings against America's Taylor Townsend and the 19th seed marked the occasion with a 5-7, 6-2, 6-2 win.
"It's cute," said the Spaniard. "It's not small, but it's, you know, cosy."
Other winners on the first day included Japanese seventh seed Kei Nishikori, a quarter-finalist in 2015, who eased past France's Quentin Halys 6-2, 6-3, 6-4. However, Italian 16th seed Marco Cecchinato, the man who sent Novak Djokovic crashing out in the quarter-finals in 2018, fell at the first hurdle.
