Roger Federer was briefly rattled before he swiftly moved into the third round of the French Open with a 6-7 6-1 6-0 6-4 win over Spaniard Albert Montanes.

The world number one, bidding for the only Grand Slam trophy missing from his collection, looked nonchalant in a scrappy first set before punishing his opponent with a string of winners.

The Swiss top seed will face Croatian Mario Ancic for a last-16 spot.

He also remained on course for an all Swiss quarter-final clash with Stanislas Wawrinka after the ninth seed breezed past Croatian Marin Cilic 7-6 7-6 6-1.

With the heavy conditions favouring Montanes's game, Federer took almost an hour to adjust.

World number 60 Montanes earned two set points on Federer's serve at 5-4 in the first set but the Swiss managed to save both -- belting down a service winner followed by an ace - just before the players had to run for cover as the showers once again returned to Roland Garros.

Following the 90-minute rain disruption, Montanes picked up where he had left off and earned two more set points in the ensuing tiebreak. He clinched it 7-5 when the world number one sent a backhand long.

Federer punished Montanes's audacity with a series of 18 winners to level the match 29 minutes later.

Another 19 minutes flashed by and the 26-year-old Swiss had earned a two-sets-to-one advantage.

Montanes briefly rallied in the fourth set but could not recover from an early break as Federer wrapped it up with an ace after two hours and 25 minutes.

Three-times champion Rafael Nadal also made light of yet another rain interruption to coast into the third round with a 6-4 6-0 6-1 victory over qualifier Nicolas Devilder.

Nadal, whose first-round match spanned two days because of the weather, was stretched by the sprightly Frenchman in the opening set but reeled off 13 straight games before cruising through in an hour and 54 minutes.

Nadal, who improved his Roland Garros record to 23-0, broke for a 4-2 lead in the opener but Devilder responded immediately with a break of his own.

The Spaniard sealed the first after 51 minutes on his second set point when Devilder netted a backhand serving at 4-5.

The second seed reeled off the next five games before the rain came and after a 90-minute break went on to book a place in round three against 26th seed and fellow left-hander Jarkko Nieminen of Finland.

Earlier on Thursday, Argentina's sixth seed David Nalbandian threw away a two-set lead to lose 3-6 4-6 6-2 6-1 6-2 to wildcard Jeremy Chardy.

The former Wimbledon finalist seemed to be cruising towards a third-round berth against Russia's Dmitry Tursunov but world number 145 Chardy hit back brilliantly and recovered from 2-0 down in the fifth to win.

Nalbandian took the first two sets in 83 minutes before Frenchman Chardy, roared on by a partisan crowd on Court Two, broke serve in game six of the third set to turn the tide in his favour.

A string of dashing winners flew from the 21-year-old's racket and he reached the third round for the first time when Nalbandian netted a backhand on his second match point after three hours three minutes.

Seventh seed James Blake's hopes were also ended prematurely when he was beaten 7-6 3-6 7-5 6-3 by Latvian teenager Ernests Gulbis.

Blake, one of five American men to reach the second round, had been hoping to join compatriot Wayne Odesnik in the last 32 but was bounced out by an opponent who hails from a family of basketball players.

World number 80 Gulbis had won back-to-back matches just twice this year before arriving in Paris, but chalked up his first win over a top 10 player this season.

A backhand down the line winner sealed Blake's fate after two hours and 36 minutes and the 19-year-old will next face either Nicolas Lapentti of Ecuador or American Bobby Reynolds.

Fourth seed Nikolay Davydenko turned the eagerly anticipated match-up with fellow Russian Marat Safin into a damp squib by recording a comfortable 7-6 6-2 6-2 victory.

Davydenko saved three set points serving at 4-5 in the opening set but after that the two-time semi-finalist breezed through the tiebreak before wrapping up the second-round match in two hours and 16 minutes on Court One.

Davydenko, who had won their three previous meetings, sealed a place in round three against Croatian 28th seed Ivan Ljubicic when Safin planted a forehand into the net.

Lleyton Hewitt eased to a 6-4 6-3 6-2 second-round win over American Mardy Fish at the French Open.

The Australian had been sidelined during the entire claycourt season in the run-up to Roland Garros but did not feel any ill effects as he battered Fish in a shade over two hours.

He will face Spain's David Ferrer, who only lost one game when he hammered usually entertaining Frenchman Fabrice Santoro .

Gael Monfils beat Peruvian Luis Horna 7-6 6-4 7-5 to progress to the second round.

Despite being broken late in the third set, Monfils - from Paris - won four games in a row to battle back from 5-3 down and clinch the match.

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Reuters