Ukrainian ninth seed Elina Svitolina overcame a tricky first-round draw by beating seven-time Grand Slam champion Venus Williams in straight sets at the French Open.

Both players struggled on serve before 24-year-old Svitolina finished both sets stronger to win 6-3 6-3.

American Williams, 38, has not gone past the third round of a Slam since reaching the 2017 US Open semi-finals.

Svitolina will play compatriot Kateryna Kozlova, the world number 67, next.

Svitolina, 24, missed two match points before sealing victory at the third opportunity when Williams sprayed a backhand into the tramlines.

The Ukrainian, a two-time Roland Garros quarter-finalist, has seen her season disrupted by a knee injury but showed little sign of any lingering problem as she won in one hour and 13 minutes.

Yet going into the second Grand Slam of the year, she had not won not the clay – which she describes as her most natural surface – after successive defeats in Madrid and Rome.

That led to her jokingly describing the draw against the veteran American as more “punishment”.

However, it was the Ukrainian who did the punishing as she managed to grind down Williams.

The pair exchanged five successive breaks of serve in their opening set, Svitolina holding for 5-3 and breaking again for a one-set lead, as 18 unforced errors flew off Williams’ racquet.

And, after Williams led 3-1 following some more erratic service games, Svitolina won five successive games to continue her record of reaching the second round in each of her main-draw appearances at Roland Garros.

Svitolina wins on new ‘garden’ court

The first-round match between one of the game’s greats and a seed rated an outside chance of winning the tournament was always going to go on one of Roland Garros’ show courts.

So organisers opted to put the match on the new Court Simonne Mathieu, showcasing an arena which they say is the “only plant ecosystem of its kind in the world”.

Named after France’s second most successful female player, the court is semi-sunken and surrounded by four greenhouses which house tropical plants from South America, Africa, South East Asia and Australia.

However, Svitolina said walking to the court – where spectators wander freely on narrow gravel paths through the gardens – was a “little bit uncomfortable”.

“Today I won and it was nice to go through the crowd, but I think when you lose that’s very, very disturbing, I would say,” she said.

“The court itself is beautiful. I really enjoyed the bounce of it and I think the crowd is great, especially when it’s a full house.”

The first match on the court was Garbine Muguruza’s victory over American Taylor Townsend and the Spaniard was enthusiastic about her surroundings.

“It’s in a very different place,” said the former Wimbledon champion. “You don’t feel like you are around a court. It’s like in a garden. It’s a different feeling. It’s not small, but it’s cosy.”

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Wimbledon champion Angelique Kerber said the pain from an ankle injury was “not my excuse” after her shock first-round exit at the French Open.

The German fifth seed lost 6-4 6-2 to world number 81 Anastasia Potapova.

The three-time Grand Slam champion said she “did not have much expectation” after pulling out of the Madrid and Rome clay tournaments this month.

Elsewhere, Spanish 19th seed Garbine Muguruza came from a set down to beat American Taylor Townsend 5-7 6-2 6-2.

Muguruza was broken for a second time late in the first set by the world number 83 but breezed through to win the next two sets in the first main draw match on the new Simonne Mathieu court.

The 2016 French Open champion will play Sweden’s world number 172 Johanna Larsson in the second round, following her victory over Slovak Magdalena Rybarikova.

Russian Potapova, playing in her first French Open, faces Marketa Vondrousova of the Czech Republic next.

“My phone is exploding at the moment,” said a delighted Potapova after her surprise win.

Meanwhile, Czech second seed Karolina Pliskova eased into the next round with a straight-set victory over Madison Brengle.

The 27-year-old, who reached the semi-finals at Roland Garros in 2017, won 6-2 6-3 to set up a meeting with Slovakian qualifier Kristina Kucova.

Last year’s runner-up Sloane Stephens also progressed on Sunday, with the 26-year-old American winning a tie-break in the second set to beat Japan’s Misaki Doi 6-3 7-6 (7-4).

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Kerber, who was bidding for a career Grand Slam, had played only three matches in the current clay-court season before coming to Roland Garros.

She admitted two weeks ago she was unsure she would be able to compete.

“At the end I didn’t have much expectation for the tournament. And I think the feeling I had before the tournament was right,” she said after her defeat on Philippe Chatrier court.

“I was able to practise in the last few days really good, but it was not a long clay-court preparation with everything. At the end, I was just happy to at least go on court, playing a match, and of course it is not like I hoped for.”

On whether she was suffering pain, she added: “It is not my excuse, I tried my best. I know there is still a little bit of work to do to play matches 100%, into sliding, to jumping on the foot, and on the leg.”

Roger Federer made a winning return to the French Open with a dominant first-round victory over Lorenzo Sonego.

The Swiss 20-time Grand Slam winner, playing at Roland Garros for the first time in four years, beat the Italian 6-2 6-4 6-4.

He arrived to a standing ovation on Philippe Chatrier court and left with the crowd on their feet in delight.

The 37-year-old will play German lucky loser Oscar Otte, ranked 145th in the world, in the second round.

“I knew I can play very well on clay and I am very happy I did it in straight sets today,” Federer said.

“I missed the French crowd so thanks for the warm welcome today.”

• Kerber suffers shock first-round defeat
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Four years away – 101 minutes to first victory

The rapturous reception he received was the only clue that Federer had ever been away from the Paris clay-court Grand Slam tournament.

The third seed missed the 2016 event with a back injury and skipped the past two clay-court seasons to preserve his body.

He raced to a 4-0 lead in the opening set before Italian world number 73 Sonego finally held his serve.

But while Sonego temporarily stemmed the flow, Federer marched on to claim the opening set in just 24 minutes.

“Two breaks in the first set was very important for me and when I was leading 4-0 I could take more risks and play more aggressive,” Federer said.

He had looked like he was going to race away with the match until Sonego began to find some form when he was a double break down midway through the second set.

A cross-court forehand winner set up three break points for the Italian, all of which Federer saved before Sonego snatched the break when the Swiss double-faulted.

The 24-year-old celebrated the breakthrough as if he had won the match – and was soon fist-pumping again when a delightful lob had Federer well beaten to seal a hold in the next game.

But the brief glimmer of hope for the Italian was soon stamped out as Federer wasted no time in a hold to love to take the second set.

A closely contested third set was effectively decided by a thundering Federer backhand across the court that gave him a break for 5-4 and he went on to wrap up the match when Sonego sent a service return wide in the next game.