Federer relieved after seeing off Ferrer
Roger Federer eased through to a 10th semi-final at the Barclays ATP World Tour Finals to leave David Ferrer and Juan Martin Del Potro scrapping for the second spot in Group B.
Federer took a 13-0 head-to-head record against Ferrer into Thursday's match at London's O2 Arena and did not really look in any danger of a first ever loss to the Spaniard as he came through 6-4 7-6 (7/5).
While an advantage in head-to-head record is obviously a confidence boost, Federer said "Streaks have ended for me at the World Tour Finals. There was Davydenko and (Fernando) Gonzalez as well years ago when he beat me for the first time."
He went on: "In some ways it's helpful to have that one-sided head-to-head record, but at the same time it sometimes creates pressure as well. You always feel like this next match it is probably going to happen.
"You try hard, he tries harder too because all he needs is that one win, so then he's got that.
"I tried hard to not make it happen today. You could feel that he's confident, he's on a run. I think it's a great victory for me."
Ferrer felt he missed his opportunity to pile pressure on Federer at the start of the match when the Swiss star was not serving well but still moved into a 3-0 lead before his opponent eventually broke back at the eighth time of asking.
Ferrer said: "I had a lot of chances to break him but I couldn't do it. When he has one break point on my serve, he makes it.
"Sometimes with these players, if I don't take my chance, I don't win the important points, it is very difficult to win these matches."
Ferrer will still have a good chance to reach the semi-finals if he beats Janko Tipsarevic in his final round-robin match on Saturday, and if he then makes the final he will overtake injured compatriot Rafael Nadal to become world number four.