Reigning champion Ana Ivanovic stuttered through the first round while Andy Murray, Marat Safin and Lleyton Hewitt all began their French Open trips on high note on Sunday. World number one Ivanovic was made to sweat more than two hours before clinching a 7-6 (3), 6-3 victory over unseeded Italian Sara Errani, who has never won a match at Roland Garros.

On men's side, big names Murray of Britain and Spaniard Fernando Verdasco comfortably took their places in the next round. The world No. 3 Briton smashed Juan Ignacio Chela of Argentina 6-2, 6-2, 6-1 and Verdasco, eighth seed, thumped France's Florent Serra 6-2, 6-1, 6-4, smacking 15 aces and 50 winners to underline a strong performance.

Two former world number ones Safin, 29, and Hewitt, 28, notched up points for the old guns in contrasting styles with the Russian beating inexperienced Frenchman Sidorenko in straight sets and the Australian conquering big-serving Ivo Karlovic with a remarkable fightback.

On what is certainly not his favorite surface, giant Croatian Karlovic still managed to rip a record 55 aces in his loss. Hewitt, trailing two sets down, displayed characteristic courage and turned the tide to win 6-7 (1), 6-7 (4), 7-6 (4), 6-4 and 6-3.

"To play Karlovic on any surface is hard especially when his ace-count is up in the 50s," said 50th-ranked Hewitt, who underwent hip surgery in August last year.

"After losing the tiebreakers it's more of a mental battle. You have to hang in there and go the distance."

Home player Amelie Mauresmo, No. 16 seed, became the biggest upset of the day, crashing out after a 6-4, 6-3 defeat by Anna-Lena Groenefeld of Germany.

Ivanovic's title defence had a bumpy start as the eighth seed had to fight a tiebreaker before watching Errani commit two uncharacteristic unforced errors to end the 72-minute first set.

With much more confidence in the second, she did not waste much time to close out the contest on third match point.

The 21-year-old will now play Thailand's Tamarine Tanasugarn or Camille Pin of France for a place in the third round.

Ivanovic, who missed last week's Madrid Open because of a knee injury, had the problem area taped when she walked onto court, but it did not hinder her in the early exchanges as she moved 3-1 ahead.

Then she was struggling a bit with her serves and a gritty Errani. While trailing at 5-4, the champion nailed a series of brilliant forehand winners to force a tiebreaker before winning it convincingly.

"Obviously I expected a tough match. I knew I had to work hard for my points today, and I'm happy I did that," said Ivanovic.

"I think this match is going to be a good test, but I feel good. I had really good practice sessions from the beginning of the year. I was working really hard.

"So even though I had some time off during the Madrid tournament, I feel like it takes only few days to get back in shape. I feel very fit," she said.

Ivanovic, who was the top-ranked player for 12 weeks in 2008, has dropped to No. 8 in the world ranking but believed she had chances to repeat her feat at Roland Garros last year.

"I did it in the past so I believe I have time to do it again. I love playing here on these courts on the clay. I just have to keep my head down and work tough through the matches," she said.

"There are so many players who want to achieve the same thing, but I believe I have quality and I

have to go with this confidence for each match."

The 25th-seeded Li Na of China became the first player to reach the second round after a 6-4, 6-2

quick win over Poland's Marta Domachowska.

The 27-year-old, who missed the Australian Open and withdrew from this week's Strasbourg because of injury, needed just 72 minutes to make the second round where she will face Switzerland's Timea Bacsinszky.

Five Russians moved into the next round including Nadia Petrova, who cruised through to a possible second round clash against compatriot Maria Sharapova.

The 11th seed beat Lauren Embree 6-1, 6-2. She clearly dominated the game as she hit 27 winners to her opponent's three.

Petrova was joined by fellow Russians 17-year-old Anastasia Pavlyuchenkova, the 27th seed, and 18-year-old qualifier Vitalia Diatchenko.

Reigning champion Ana Ivanovic stuttered through the first round while Andy Murray, Marat Safin and Lleyton Hewitt all began their French Open trips on high note on Sunday. World number one Ivanovic was made to sweat more than two hours before clinching a 7-6 (3), 6-3 victory over unseeded Italian Sara Errani, who has never won a match at Roland Garros.

On men's side, big names Murray of Britain and Spaniard Fernando Verdasco comfortably took their places in the next round. The world No. 3 Briton smashed Juan Ignacio Chela of Argentina 6-2, 6-2, 6-1 and Verdasco, eighth seed, thumped France's Florent Serra 6-2, 6-1, 6-4, smacking 15 aces and 50 winners to underline a strong performance.

Two former world number ones Safin, 29, and Hewitt, 28, notched up points for the old guns in contrasting styles with the Russian beating inexperienced Frenchman Sidorenko in straight sets and the Australian conquering big-serving Ivo Karlovic with a remarkable fightback.

On what is certainly not his favorite surface, giant Croatian Karlovic still managed to rip a record 55 aces in his loss. Hewitt, trailing two sets down, displayed characteristic courage and turned the tide to win 6-7 (1), 6-7 (4), 7-6 (4), 6-4 and 6-3.

"To play Karlovic on any surface is hard especially when his ace-count is up in the 50s," said 50th-ranked Hewitt, who underwent hip surgery in August last year.

"After losing the tiebreakers it's more of a mental battle. You have to hang in there and go the distance."

Home player Amelie Mauresmo, No. 16 seed, became the biggest upset of the day, crashing out after a 6-4, 6-3 defeat by Anna-Lena Groenefeld of Germany.

Ivanovic's title defence had a bumpy start as the eighth seed had to fight a tiebreaker before watching Errani commit two uncharacteristic unforced errors to end the 72-minute first set.

With much more confidence in the second, she did not waste much time to close out the contest on third match point.

The 21-year-old will now play Thailand's Tamarine Tanasugarn or Camille Pin of France for a place in the third round.

Ivanovic, who missed last week's Madrid Open because of a knee injury, had the problem area taped when she walked onto court, but it did not hinder her in the early exchanges as she moved 3-1 ahead.

Then she was struggling a bit with her serves and a gritty Errani. While trailing at 5-4, the champion nailed a series of brilliant forehand winners to force a tiebreaker before winning it convincingly.

"Obviously I expected a tough match. I knew I had to work hard for my points today, and I'm happy I did that," said Ivanovic.

"I think this match is going to be a good test, but I feel good. I had really good practice sessions from the beginning of the year. I was working really hard.

"So even though I had some time off during the Madrid tournament, I feel like it takes only few days to get back in shape. I feel very fit," she said.

Ivanovic, who was the top-ranked player for 12 weeks in 2008, has dropped to No. 8 in the world ranking but believed she had chances to repeat her feat at Roland Garros last year.

"I did it in the past so I believe I have time to do it again. I love playing here on these courts on the clay. I just have to keep my head down and work tough through the matches," she said.

"There are so many players who want to achieve the same thing, but I believe I have quality and I

have to go with this confidence for each match."

The 25th-seeded Li Na of China became the first player to reach the second round after a 6-4, 6-2

quick win over Poland's Marta Domachowska.

The 27-year-old, who missed the Australian Open and withdrew from this week's Strasbourg because of injury, needed just 72 minutes to make the second round where she will face Switzerland's Timea Bacsinszky.

Five Russians moved into the next round including Nadia Petrova, who cruised through to a possible second round clash against compatriot Maria Sharapova.

The 11th seed beat Lauren Embree 6-1, 6-2. She clearly dominated the game as she hit 27 winners to her opponent's three.

Petrova was joined by fellow Russians 17-year-old Anastasia Pavlyuchenkova, the 27th seed, and 18-year-old qualifier Vitalia Diatchenko.