Looking back at Roger Federer's last 5 semifinals at the ATP Finals

#4 2014 Semifinals: Beat Stan Wawrinka 4-6 7-5 7-6(6)

Federer beat Wawrinka in the 2014 ATP Finals semifinals

Federer breezed through the group stage without dropping a set, beating Milos Raonic, Kei Nishikori and Andy Murray to reach a 12th semifinal at the ATP Finals. There, he met the reigning Australian Open champion and good friend Stan Wawrinka.

Federer dropped his first set of the tournament as Wawrinka took a one-set lead. The 17-time Grand Slam champion then fought back to take the second set 7-5 to force a decider.

In a highly competitive third set the momentum shifted back and forth as Federer, irked by an over-rule by the chair umpire, dropped serve in the opening game.

Wawrinka squandered three match points when serving for the match at 5-4 as the match went to a tiebreak. The 'other Swiss' saw another match point come and go before Federer made good on his first opportunity to reach his ninth final at the ATP Finals.

#5 2013 Semifinals: Lost to Rafael Nadal 5-7 3-6

Nadal beat Federer in the 2013 semifinals

Having lost to Novak Djokovic in his opening round-robin match, Federer beat Richard Gasquet in straight sets before recovering from 0-3 down to beat Juan Martin del Potro 7-5 in the third and reach his 11th semifinal at the ATP Finals.

Facing Rafael Nadal for the fifth time in the tournament, Federer looked to seize the early initiative but lost serve at 4-4 as Nadal rained down some ferocious forehands. Federer fought back in the next game to get back on serve, only for Nadal to ride on another errant service game from Federer to take the opening set 7-5.

Federer continued to struggle on serve in the second set, dropping serve at 2-2. He got broken again in the ninth game of the set as Nadal registered his first victory at the ATP Finals in five attempts over the six-time champion.

Nadal went on to lose to Djokovic in the final.