• ATP World Tour Finals

Federer fit and firing after opening win

Roger Federer believes he has justified the decision to skip last week's Paris Masters after sailing through his ATP World Tour Finals opener in London.

Federer claimed a record 40th match win in the year-end championships with a 6-3 6-1 victory over Janko Tipsarevic, and he believes the week off to rest injury niggles enabled him to be ready just in time.

His decision not to defend his Masters 1000 title gifted Novak Djokovic the year-end No. 1 ranking, but Federer has no regrets about pulling out as he declared himself injury free for the season finale.

"I'm happy that I feel fine just in time," Federer said following his victory over Tipsarevic on Tuesday. "I still had some little things I had to work through the last couple of days.

"Really since yesterday I feel fine. So obviously it was good for me to start on Tuesday. I'm happy with my performance today. No pain anymore anywhere. I'm happy with my level of play today against Janko, who is obviously a good player."

Federer will expect to face tougher tests in the shape of Paris Masters champion David Ferrer and Juan Martin Del Potro, who beat him in the Swiss Indoors final last month.

The last time Federer played Del Potro in a round-robin clash at the 2009 event, the Swiss lost the match but went on to reach the semi-finals at the expense of Andy Murray. This time around, he is hoping to avoid any complicated calculations and ensure his place in the semi-finals with three victories to win Group B outright.

"What I didn't like about that match in 2009, was we didn't know who came through and not, because it was a matter of games," Federer said. "It was Murray, me, and Del Potro.

"I kind of was aware of it while I was playing that if I get a set, I'm done, I'm through. I still had chances in the third set to break and should have won. I ended up losing. That created the whole chaos.

"It was an interesting situation and really hard to focus on just the match. That obviously sometimes happens in the round robin."

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