Two-time defending champion Novak Djokovic and six-time champion Roger Federer will meet in the final f the 2014 Barclays ATP World Tour Finals, after Federer edged fellow countryman Stan Wawrinka in the semi-final stage of the tournament.

In what was undoubtedly the most enthralling match of the year-end championships so far this season, Federer and Wawrinka contested a three-set battle that featured an assortment of controversy, overrules, momentum shifts, and heartbreak, before Federer eventually struck the final blow for a 4-6, 7-5, 7-6(8) score.

The first set saw a quick break from Wawrinka to lead 3-1. His backhand appeared dialed in and he was continued to attack Federer until he extended the gap to 5-2 with a double break advantage. While Federer managed tighten the score by snatching one of the breaks back, Wawrinka managed to serve out the set on his second attempt to set up what was likely to become the most competitive match of the tournament yet.

While the first set saw Wawrinka take command of the action and control the court, the second set was a far more competitive affair, and while both men had break point chances, the score remained on serve through ten games. However, the 17-time Grand Slam champion pounced late in the set to win the next eight consecutive points and force the contest to a decider.

The final set started in controversial fashion, as Federer did not notice the chair umpire overrule his point at 30-0, and found himself down 0-40 on serve without being mentally prepared for it. Wawrinka pounced and snatched an early break before extending his lead to 3-1 shortly thereafter. The Swiss No. 2 held his nerve during service games until it came time to serve out the match at 5-4 up. There, a lengthy game would see Federer break serve and quickly take a 6-5 lead in the final set. Moments later, the match was forced into a tiebreak, which Federer won after saving a fourth match point.

Federer will now contest the final in London against two-time defending champion Novak Djokovic.