Federer happy to be second in world after great season
Roger Federer insists he has no regrets despite missing out on finishing the year as World No.1.
Federer's decision to skip the Paris Masters last month ended any hopes he may have had of catching Rafael Nadal at the top of the rankings.
Nadal subsequently withdrew from this week's ATP Finals in London after just one match through injury, clearing a path for Federer to claim a seventh title and the potential 1,500 ranking points on offer.
Yet victory in the final on Sunday would leave the 36-year-old Swiss superstar still 140 points shy of his great Spanish rival.
However, Federer said: "Regrets? I don't have any. But maybe losing to Tommy Haas (in Stuttgart) and Evgeny Donskoy (in Dubai) ended up haunting me.
"I had match points in both matches. It's not like I didn't try.
"To have regrets because of these matches - if I miss out because of that for World No.1 then maybe I was unlucky.
"But I also did win matches in Miami, saving match points against Tomas Berdych, and other matches throughout the season could have gone either way as well.
"So I'm just happy I'm playing a great season. I'm so happy that I was able to reach this level of play and still being able to play also at the end of the year.
"I have no regrets because I totally exceeded my expectations. I'm just happy that I'm injury-free and healthy right now and enjoying myself still."
Federer did not appear to be enjoying himself a great deal after finding himself a set behind and facing a break point against already-eliminated Marin Cilic in yesterday's final round-robin game.
Having qualified for the semi-finals regardless of the result, the 19-time Grand Slam winner could have been forgiven for taking a rare defeat on the chin and saving himself for tomorrow's more important meeting with either Dominic Thiem or David Goffin.
Yet, ever the perfectionist, Federer dug deep to run out a 6-7 (5/7) 6-4 6-1 winner ahead of his 14th semi-final in 15 appearances at the London Finals.
Cilic, who endured a painful defeat to Federer in July's Wimbledon final a few miles along the Thames, said: "I think today was a solid match.
"Obviously it's a little bit more difficult mentally knowing that I'd had two losses, and that I wasn't going to be able to go through.
"But still I played those first two sets at a really good level. I even had a break point there early in the second.
"In the third set I felt like I dropped a little bit with my serving percentage. Once Roger got the break he was playing little bit looser. He obviously played well."
• AMERICA'S Jack Sock emerged on top after a thrilling battle with German wonderkid Alexander Zverev to make it into the last four in the final game of yesterday's action.
In what was an eliminator in the group, with Roger Federer already through as winner, Sock was victorious, taking the match 6-4 1-6 6-4 thanks to an unforced error from the 20-year old.
He will now face Grigor Dimitrov in the semi-finals, while Federer will have to wait until today to find out his last four opponent.