体坛英语资讯：Federer reaches quarters of Qatar Open

Second seed Roger Federer reached the quarterfinals of the Qatar Open on Wednesday by beating Swiss teammate Marco Chiudinelli 7-6(5), 7-5.

The 16-time Grand Slam champion needed a tiebreaker in the first set and a strong baseline game in the second to register his second straight win in Doha, where he is looking for his third tournament title.

"It was really difficult today, under the circumstances," admitted Federer. "Playing such a good friend is so rare for me. I'm happy the match is in the past and I can look forward."

Federer will next meet Serbia's Viktor Troicki after the sixth seed struck 17 aces past Russia's Teimuraz Gabashvili in a 6-3, 6-1 win.

"I think we've only played once, if I'm correct. I hardly heard of him before then. Obviously he's improved since then. He's beaten some good players, so I'm sure it's going to be a tough match."