Roger Federer stumbled his way to an unconvincing 6-3, 2-6, 6-4 victory over Argentine qualifier Juan Monaco in the second round of the Hamburg Masters on Tuesday.

The Swiss World number one looked comfortable in the first set, played under the roof with the rain lashing down outside, but hit more and more unforced errors as Monaco levelled the match in a second set he dominated.

Federer, the top seed at the 2.1 million euros clay-court tournament, then had to save five match points in his first service game in the decider before eking out a break for 5-4 and clinching victory in one hour 56 minutes.

It was Federer's first match since splitting with his part-time coach Tony Roche at the weekend and it is clear he will need to improve if he is to challenge Rafael Nadal for the French Open, which starts on May 27.

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

He goes on to face either Marat Safin or Juan Carlos Ferrero in what should be a good test in the third round.

Hewitt looks sharp

Lleyton Hewitt, looking sharp after a practice session with Rafael Nadal, continued his comeback from injury with a 6-2, 7-6 victory over Juan Ignacio Chela in the second round.

The Australian, who hit with the Spanish clay court supermo the day before the match, broke Chela in his opening service game and hardly looked back as he went a set and a break up.

He was briefly in trouble as Chela clawed the break back and the former world number one had to save two set points when 5-6 down. He managed to hang in and force a tie-break, winning it 7-3 with a punched half-court forehand on match-point.

Hewitt, the former world number one, came into the 2.1 million euros clay-court tournament with just one match under his belt in two months.

After two victories over crafty claycourt players -- he beat another Argentine, Agustin Calleri in the first round -- he was highly pleased with his start in Hamburg.

"I played very well," Hewitt, who now rates himself fully fit, said at a news conference. "I stepped up another notch form the first round."

"The practice with Nadal was good," added Hewitt, who is the 16th seed in Hamburg. "He's the stand-out player on this surface. Roger is great on any surface but Nadal takes it to another level on clay, and I feel I hit it well with him."

Hewitt will go on to face either Russia third seed Nikolay Davydenko or Frenchman Gilles Simon in the third round.

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