Rain is expected to descend on Roland Garros today and, off and on, for the rest of the week, so it's advantage to those players who managed to get through their first-round matches at the French Open yesterday.

Given Paris's love affair with Roger Federer, it was no surprise that the 2009 champion should be among those to enjoy a quick passage through on day one. Eight-time champion Rafael Nadal, meanwhile, will not only have to play today, if he can dodge the rain clouds, but has also been handed the ignominy of not being put on the main show court.

The relationship between Nadal and the Roland Garros crowd has ranged from a love affair to a divorce hearing, with the world No.1's uncle, Toni Nadal, once having accused them of being anti-Spanish. So Nadal will begin his quest for a record-extending ninth French Open title against the veteran American Robby Ginepri on Court Suzanne Lenglen, a brisk five-minute walk from the ­players' lounge.

The American John Isner, who knows Ginepri well, was as shocked as everyone else to learn that the Nadal-Ginepri match would not be on the main court. "That's really bizarre," said the man to reach round two with an opening-day win. "I mean, how many times does the guy have to win the tournament to be able to have his first match on Chatrier?

"I think, no offence to Stan [Wawrinka, who is playing on Chatrier], but, you know, if you look at it, figured they'd be flip flopped. But I don't think Rafa really cares that much. He's just going to go out there and try to win.

"I know he's playing Robby, super good friend of mine. I believe Robby got up at 8:00 in the morning to hit on Chatrier this morning. And [now] he's not playing on there."

Federer had no such worries yesterday as he brushed aside the Slovak Lukas Lacko 6-2, 6-4, 6-2 to reach the second round, where he will play the little-known Argentine Diego Sebastian Schwartzman.

Seeded fourth, Federer has been more consistent this year than last, helped by the fact that his back is no longer a problem. The Swiss has been there and done everything in the game and is not about to get ahead of himself as he tries to add to his 17 grand slam titles, just a couple of weeks after becoming the father to a second set of twins.

"I don't get too worked up about it because I know it's a long match maybe potentially ahead of me and it's not a sprint to the finish line, it's more of a marathon," he said, looking ahead to the battles to come."

In his "old age", the 32-year-old Federer has become more comfortable saying whatever he wants, unafraid to upset anyone. So when he was asked whether the fact that Nadal had won only one of the main three European clay-court events meant he was less of a favourite than normal in Paris, Federer was quick to respond. "I don't know who's talking all the time, but Rafa is the favourite, then Novak, and then the rest, you know," he said. "It's very clear. But it doesn't matter who is the favourite or not. We will see in a few weeks. Really doesn't matter one bit."

The Sunday start remains a talking point in Paris, eight years after the tournament introduced it, to enhance television viewers and revenue. In 2006, Federer was asked if he was willing to play on the opening day and when he refused, tournament organisers put him on the schedule anyway; it is not something Federer has forgotten.

"In a way it makes sense for tennis tournaments to start on a Saturday [or] Sunday, rather than on Monday," he said. "I don't necessarily agree that the French Open has a Sunday start and 15 days of grand slam over Wimbledon having 13, let's say."

The Williams sisters have dominated women's tennis for the best part of a decade and though Venus' star is waning, the sisters took a step towards a third-round meeting here. Serena, the defending champion and world No.1, looked as if she had just got out of bed as she ambled past Alize Lim of France 6-2, 6-1 to reach round two.

Venus, meanwhile, gained a more than creditable 6-4, 6-1 win over Belinda Bencic, a Swiss coached by Martina Hingis's mother and tipped as a future champion.

Milos Raonic, the eighth-seeded Canadian, eased into round two with a 6-3, 7-6, 6-3 win over the rising Australian Nick Kyrgios while home favourite and No.13 seed Jo-Wilfried Tsonga cruised into round two with a 7-6, 7-5, 6-2 victory over fellow Frenchman Edouard Roger-Vasselin.

Second seed Novak Djokovic, ­seeking a first French Open title, plays Joao Sousa of Portugal while Britain's James Ward takes on No.17 seed Tommy Robredo in the first round today.