Federer admits 'got lucky' post defeating Wawrinka in gripping Tour Finals' semifinal

17-time Grand Slam champion Roger Federer has admitted that he got lucky after he battled on and saved four match points before defeating compatriot Stanislas Wawrinka in the semifinals at the ATP World Tour Finals.

The six-time champion wrestled control from his Wawrinka in an all-Swiss semifinal and came through 4-6, 7-5, 7-6 (8-6) in London. He will now take on world number one Novak Djokovic in Sunday's final.

Wawrinka and Federer will team up next week as Switzerland try to win the Davis Cup in France.

It looked as though the 17-time Grand Slam champion would be heading to Lille first when his friend and teammate moved within one point of victory four times. Wawrinka served for victory at 5-4 in the decider but might regret choosing to serve-volley on three match points, missing a makeable backhand volley on the second.

The Australian Open champion earned a fourth match point in the decisive tie-break but could not return a good serve, and Federer made him pay with a nerveless drop volley on his first match point.

Federer said that he got lucky, adding that Wawrinka played better from the baseline and that usually does the job on this court, but also admitted that he kept fighting. He said that it's tough on Wawrinka but he is thrilled to be in another final in London.

Federer's deft winner brought an end to the longest, and by far the most entertaining, match of the week at two hours and 48 minutes, which kept the 17,000 spectators at the O2 Arena gripped throughout.

Wawrinka faced a considerable task to keep hold of his advantage all the way to the finish line but got within a point four times, only to fall agonisingly short of only a third win over his illustrious compatriot in 17 attempts, the report added.