Stanislas Wawrinka has become the final man to progress to the ATP World Tour Finals last four courtesy of his three-set victory over Marin Cilic at the 02 Arena.

Victory for the Swiss sees him qualify as Group A runner-up and sets up a semi-final meeting with 17-time Grand Slam champion Roger Federer in London.

Cilic still had a chance of reaching the last four himself, but could only afford to lose three games in a straight-sets victory, and that subplot was soon settled as Wawrinka stormed into a 4-1 lead.

The Swiss closed out the opener with relative comfort, but Cilic, who had not won a set in his two previous defeats at the tournament, did not roll over as the two players exchanged serve for the first nine games of the second.

The US Open champion then broke for the first time to level the match at a set apiece, and appeared to be heading for a maiden Tour Finals victory when several Wawrinka unforced errors gifted him a break early in the third.

However, Cilic could not take advantage and twice hit long as the set got back on serve, and the world number four broke again in game seven as he powered his way to a 6-3 4-6 6-3 win in 107 minutes.

Novak Djokovic earlier secured his place in the semi-finals, where he will play Japan's Kei Nishikori.