Djokovic books spot in ATP final

In the first of the semifinals in London, the world No. 1 wasted no time jumping all over his opponent. Nishikori beat Djokovic at this year's US Open, but this time the hard-serving Serb broke his opponent twice to take the first set 6-1.

Djokovic broke again to open the second set but handed his advantage straight back with a double-fault. And Nishikori used precise ground strokes to maneuver the two-time defending ATP champion around the court and get another crucial break. The Japanese player leveled the encounter with a 6-3 win in the second set.

But Djokovic slammed the door in the Japanese player's face in the most decisive fashion possible, handing him a bagel in the third set to earn a 6-1, 3-6, 6-0 victory and clinch a place in final of the end-of-the-year men's tennis tournament.

"Kei was playing great and this has been the best season of his life, but he made some crucial double faults in the third set," Djokovic said after the match.

An all-Swiss thriller

The other semi-final featured second-seeded Roger Federer and his Swiss Davis Cup teammate Stan Wawrinka in a battle of big servers. And Wawarinka got off to the better start, breaking Federer early on and winning the first set 6-4.

But Federer, who has won more Grand Slam events than any other man in history, stiffened his resistance and held on to take a very tight second set 7-5. Wawrinka led the way in aces, but put less than half of his first serves in play.

In the third and deciding set Wawrinka got an immediate break and had the chance to put Federer on the ropes when he took the lead in the crucial seventh game. Federer held on, though, to stay in contention. Federer had the chance for a break-back in the next game, but Wawrinka prevailed after multiple deuces.

Federer was able to fend off three match points with Wawrinka serving and broke his countryman to level the set at five games apiece. The match came down to a tie-breaker, with the veteran Federer holding his nerve. The final score was 4-6, 7-5, 7-6 (8-6).

Federer has the chance to win his seventh ATP title. But regardless of the outcome of the final Djokovic will end the 2014 season ranked number one.