HAMBURG, Germany (AFP) - Defending champion Roger Federer and Australian Open winner Novak Djokovic cruised into the Hamburg Masters semi-finals on Friday with straight-set wins.

World number one Federer always looked comfortable as he beat Spain's Fernando Verdasco 6-3, 6-3 in 80 minutes and will face Italy's Andreas Seppi, ranked 43rd in the world, on Saturday for a place in the final.

Verdasco, 28th in the world, had removed fifth-seed David Ferrer and tenth-seeded Russian Mikhail Youzhny in previous rounds but a foot injury in the second set compromised his bid to oust his Swiss opponent.

"It was quite a tough match, he's a very talented player who is capable of beating any player on any surface, I had to work hard," said Federer.

"I thought he would come out and go for aces, but he hit some great shots off his backhand."

Seppi came out on top 6-3, 5-7, 7-5 in a marathon three hour 13 minutes contest against home hope Nicolas Kiefer in a quarter-final where both players served for the match.

Roared on by the crowd, Kiefer bounced back from being 6-3, 5-3 down in the second set to serve for the match at 5-4 up in the third.

But Seppi held his nerve to deny Kiefer the opportunity to become the first German in the semi-finals here since 1997.

Earlier, world number three Djokovic was always in control against Spain's Albert Montanes as he sealed a 6-2, 6-3 win in 77 minutes and will play either world number two Rafael Nadal or Carlos Moya in Saturday's semi-final.

"I didn't want to underestimate my opponent, but I was conscious of saving energy and keeping something back for the semi-final," said the Serb.

Djokovic will take Nadal's place as world number two behind Federer if he beats the Spaniard in Saturday's semi-final or Nadal loses to Moya in the quarter-final.

Federer has won four of the last six tournaments in Hamburg and beat triple French Open champion Nadal in last year's final.

The Swiss star admitted it was good experience to face left-handed Verdasco, especially if he plays Nadal again in Sunday's final.

"It's always good to face left-handed players, especially with Roland Garros coming up," he said.

"If you face a left-hander in Paris it always helps if you have faced one a week ago rather than five months before."