ROGER FEDERER has refused to look past his Wimbledon semi-final opponent Tommy Haas - despite standing just two matches away from breaking Pete Sampras's record of 14 Grand Slam triumphs.

By Hugh MacDonald

ROGER FEDERER has refused to look past his Wimbledon semi-final opponent Tommy Haas - despite standing just two matches away from breaking Pete Sampras's record of 14 Grand Slam triumphs.

The five-time Wimbledon winner was in imperious form as he dismissed giant Croat Ivo Karlovic with a convincing 6-3, 7-5, 7-6 victory.

But Federer insists he is keeping thoughts of making tennis history firmly in the back of his mind.

The second seed's semi-final appearance is Federer's 21st consecutive appearance in the last four of Grand Slams.

But the Swiss world No.2 said: "I'm happy the way I'm playing, which is always most important.

"My mind has not started wondering yet. I think tomorrow I'll prepare for a tough weekend ahead of me.

"It would be writing in the history books of tennis but it's not there yet. It's still far away - many points, many serves, many forehands."

Karlovic had blitzed his way through to the quarter-finals by serving 137 aces and dumping out top-10 duo Jo-Wilfried Tsonga and Fernando Verdasco in the previous two rounds.

But it took only four games for Federer to break the Croatian's serve for the first time in the tournament.

And Fed said: "He's got a phenomenal serve. The way he backs it up with his volleys, it's quite something.

"It's not easy to return it, but it's thrilling because at some stage it's going to get close and that's why I was very happy the way I was able to play against him.

"I still got 23 aces, but where I'm definitely good is when it really matters, and you get maybe only a couple of chances a match.

"I thought it was an excellent match. I'm relieved I'm through."

Meanwhile, 31-year-old Haas, who has battled back from three shoulder operations, booked his first Wimbledon semi-final by knocking out fourth seed Novak Djokovic.

The 24th seed, who had never been past the fourth round in 10 previous trips to Wimbledon, secured a 7-5, 7-6, 4-6, 6-3 victory over his 22-year-old opponent to become the fourth German to reach the semi-finals in the open era.

The former world No.2 has now won 10 consecutive matches on grass after claiming a pre-Wimbledon title at Halle where he also beat Djokovic in the final.

Haas said: "It's unbelievable, there are no words for it. I'm playing my best tennis and getting this far is a great feeling. To be in the semi here really is amazing for me.

"In 13, 14 years of me playing Wimbledon, there's a lot of bad luck involved.

"There was one year when I would have been maybe seeded three, but my parents had a really bad motorcycle accident so I skipped that year.

"Then, when I had a pretty decent draw where I felt I could get far, I stepped on a ball in a warm-up and I also lost three tie-breaks against Wayne Arthurs in the third round one year.

"That's all in the past. I always felt deep down that Wimbledon will maybe still have something left for me."