PARIS -- Defending champion Maria Sharapova's bid for a third French Open title in four years is over.

Coughing between points on an overcast day, the second-seeded Sharapova was outplayed throughout a 7-6 (3), 6-4 loss to 13th-seeded Lucie Safarova of the Czech Republic in the fourth round Monday.

"My opponent had a different gear than I did," Sharapova said.

It is her earliest defeat at Roland Garros since 2010, when she was beaten in the third round. Since then, the Russian won the clay-court Grand Slam tournament in 2012 and 2014, was the runner-up to Serena Williams in 2013, and reached the semifinals in 2011.

Safarova dictated much of the action and held her nerve as the far more experienced and accomplished Sharapova tried to mount a comeback in the second set.

"Maria is an amazing player. I needed to play aggressive and to come forward for the points," Safarova said.

The left-handed Safarova wound up with a considerable edge in winners, 34-20, including forehands on the last two points to break Sharapova.

"I felt like I had small openings, and I just wasn't able to ... play a good few points. I just wasn't able to keep that level up today," Sharapova said. "She was able to do that for a longer period of time. ... She took the time away from me, created her angles and I didn't. That was the difference today, in my opinion."

She did not use the cold she's been dealing with as an excuse, saying: "I don't like to talk about it, and I don't think it really makes a difference. I'm still a competitor, no matter what."

In her first French Open quarterfinal, Safarova will face No. 21 Garbine Muguruza of Spain, who beat No. 28 Flavia Pennetta of Italy 6-3, 6-4.

Both of those fourth-round matches were originally supposed to be played Sunday, but were postponed after a rain delay in the afternoon.

They instead became part of a Monday full of tennis' biggest names, with Williams and the Big 4 of the men's game -- Roger Federer, Rafael Nadal, Novak Djokovic and Andy Murray -- all on the schedule.

Federer, whose record 17 Grand Slam titles include the 2009 French Open, needed only about an hour to finish off his 6-3, 4-6, 6-4, 6-1 victory over 13th-seeded Gael Monfils of France in a match that was suspended because of darkness after the second set Sunday night.

In truth, this one might have been over after the very first game when they resumed: Monfils led 40-love, then tried to showboat a little and got broken. Federer broke to open the fourth set, too, en route to his 11th Roland Garros quarterfinal, where he'll play Swiss Davis Cup teammate Stan Wawrinka.

Sharapova, a five-time major champion who completed her career Grand Slam in Paris three years ago, started things off at a mostly empty Court Philippe Chatrier.

Years ago, Sharapova famously described herself as a "cow on ice" when playing on red clay, troubled by the tricky footing. But she overcame that well enough to win 65 of her last 71 matches on the surface entering Monday.

Sharapova also had not lost to Safarova anywhere since 2010, winning their four most recent matches. Still, from early on, it was clear Sharapova was not going to have her way this time against Safarova, who won the Australian Open doubles title in January but whose best career showing to date in singles was a semifinal run at Wimbledon last year.

Safarova grabbed 12 of 15 points in one stretch while taking a 3-1 lead. Sharapova steadied herself and broke back, then faltered in the tiebreaker.

Safarova controlled lengthy exchanges at the baseline, opening the tiebreaker with three groundstroke winners in a row, and also benefited from Sharapova's lone double-fault of that set.

The second set began similarly, with Safarova breaking to go ahead 2-0, then holding for 3-0. But Sharapova, gritty as can be, did not give up, and when Safarova double-faulted on break point, suddenly it was 3-2.

In the next game, Safarova had a break point but flubbed a swinging forehand volley off a floater. It was a bad mistake, and Sharapova wound up holding for 3-all, yet Safarova managed to smile at her own gaffe.

She stayed calm from there, even after another bad miss on her first match point, slapping a forehand into the net.

Soon enough, though, Safarova earned a second chance to close it out, and she did.