Li Na becomes the first Chinese player to reach the quarters at Roland Garros [EPA]

Rafael Nadal reached the last eight at Roland Garros on Monday as his title rival Novak Djokovic enjoyed an even more successful day – without even playing.

The second-seeded Serb reached the semi-finals of the tournament where he potentially faces Roger Federer, after quarter-final opponent Fabio Fognini withdrew due to injury.

Top seed Nadal earned his victory the hard way, with a 7-5, 6-3, 6-3 win over Croatian veteran Ivan Ljubicic and will face Sweden's Robin Soderling in the quarters.

Andy Murray overcame ankle problems to come back from two sets down to level at 4-6 4-6 6-3 6-2 against Viktor Troicki when bad light stopped play.

Maria Sharapova reached the women's quarters with an inconsistent 7-6 7-5 win over Poland's Agnieszka Radwanska and Australian Open runner-up Li Na outlasted Czech ninth seed Petra Kvitova 2-6, 6-1, 6-3 becoming the first Chinese player to reach quarters of the clay court Grand Slam.

Record chaser

Nadal's win kept him on course to equal Bjorn Borg's record of six titles on the Parisian clay.

"I have improved since the tournament started,'' said Nadal, who was pushed to five sets in the first round.

"I'm able to play better and I'm going to continue on this path.''

Nadal was a break to the good to lead 2-1 in the opening set before Ljubucic, a 2006 semi-finalist, hit back for 3-3.

The Spaniard stepped up the pressure on the Croatian's serve, however, and snatched the set when Ljubicic sent his single-handed backhand wide.

Two breaks in the seventh and ninth games of the second set helped Nadal stretch his lead, the set secured with a smart, down-the-line whipped forehand.

A break for 3-1 in the third set seemed to be the foundation that the 24-year-old required, but Ljubicic, at 32 the oldest man left in the draw, hit back for 2-3.

But an immediate break to love gave Nadal a 4-2 lead and he claimed the tie in the ninth game when Ljubicic again went long with a loose backhand.

Chinese hero

After a lightning-quick third-round victory over Sorana Cirstea, sixth seed Li was given a much tougher test but again impressed the tennis connoisseurs on Court Philippe Chatrier with her dogged determination and weight of shot.

She battled back from an early break in the third set to prevail and prompted the suited gentlemen in the galleries to tip their panama hats in appreciation.

"It was tough, like 3-0 down in the final set. Even myself, I didn't believe I could come back, because she has a huge big serve," Li, whose husband and ex-coach could not stand the pressure, told reporters.

"So I don't know what happened. Maybe just my husband left and I could win six games in a row," she joked.

Djokovic will get an extra's day rest compared to the others in the men's draw.

Fognini pulled out of Tuesday's slated match after failing to recover from a thigh injury sustained in Sunday's five-setter with Albert Montanes.

Winning streak

Djokovic is on a 41-match winning streak since the start of the year, just one behind John McEnroe's 1984 record.

His progression through the last eight will not count as part of the streak, officials confirmed, so the world number two will have to lift the trophy if he is to break the American's mark in Roland Garros. Roger Federer could loom in the semis.

French ninth seed Gael Monfils, a 2008 semi-finalist, set-up a last eight clash with third seed Roger Federer after defeating Spain's David Ferrer, the seventh seed, 6-4, 2-6, 7-5, 1-6, 8-6.

Monfils had led by two sets to one when the tie was suspended on Sunday night and despite squandering three match points in the ninth and 11th games of the decider on Monday, the 24-year-old eventually held his nerve.

Argentina's Juan Ignacio Chela shattered Alejandro Falla's dreams of becoming the first Colombian man to reach a Grand Slam quarter-final with a 4-6, 6-2, 1-6, 7-6 (7/5), 6-2 win.

Source: Agencies