Nadal, Fed unimpressive

Nadal struggled to impose himself in the first set against fellow Spaniard Oscar Hernandez, although he eventually won 7-5 6-1.

Nadal goes on to face the Russian Igor Andreev, who was the last man to beat him on clay, back in April 2005 in the quarter-finals in Valencia.

Andreev outlasted the German Philipp Kohlschreiber 6-7 6-1 6-4 to take his place in the last 16.

"The fact that it was Andreev who beat me in Valencia doesn't make it anything special," Nadal said at a news conference. "But he's a very good player, with an unbelievable forehand and it's going to be a tough match. "I just hope the sun comes out."

Play on the centre court took place under the roof, and with the rain lashing down outside there were only a handful of completed matches on day three of the 2.1 million euros tournament.

Meanwhile, Roger Federer scraped into the third round with a 6-3 2-6 6-4 win over Juan Monaco.

World number one Federer had to save five break points to avoid going a break down in the deciding set against the Argentine qualifier before completing an unconvincing win in one hour 56 minutes.

Federer, playing his first match since splitting with part-time coach Tony Roche, did little to suggest that he will challenge Nadal at the French Open later this month.

He started with an impeccable service game and looked in reasonable shape throughout the first set but both his footwork and his usually unerring forehand deserted him as the Argentine took control.

The unforced errors kept on coming but he managed to hold on and force a break point for 5-4 in the decider, turning a desperate save into a winner down the line. Monaco conceded defeat when he let a backhand drift wide on match point.

"It was a hard fought win but maybe that was just what I needed," said Federer, who went out early in Rome last week.

"I've spent more time on the practice courts than in matches lately and I need to pick up as many wins as possible now going into the French Open."

Federer, who has never won at Roland Garros, needs to take the clay-court title to become only the third man after American Don Budge and Australian Rod Laver to hold all four majors at the same time.

The top two seeds were joined in the third round by Spain's Carlos Moya, who beat Czech 10th seed Tomas Berdych 3-6 7-5 7-6 outside before the rain started, and 16th seed Lleyton Hewitt , who beat Juan Ignacio Chela of Argentina 6-2 7-6.

Eighth seed James Blake of the U.S. beat Arnaud Clement of France 6-2 6-3, while Spanish 15th seed Juan Carlos Ferrero set up a third round match against Federer by beating the Russian Marat Safin 6-3 7-6, after taking a nail-biting second-set tiebreak 17-15.