Djokovic, who has finished year-end No. 1 in the world rankings for the second straight year, will look to win his second title at the tournament following his first win in 2008.

The Serb fought back from one set down to eliminate 2009 finalist Juan Martin del Potro 4-6, 6-3, 6-2 at the O2 Arena.

"I'm very pleased, it's the first final here in London," said Djokovic. "I haven't played a final of the World Tour Finals since 2008. I really look forward to it. It's already a great success. But knowing it's the last match of the season, I'm really going to try to give my best physically and mentally tomorrow to eventually try to get the trophy."

Djokovic has now won a personal-best 74 matches - tied No. 1 with David Ferrer for most victories on the ATP World Tour this season.

Federer, arguably the greatest player the sports has ever seen, defeated third seed Murray 7-6 (5), 6-4 in one hour and 33 minutes in the semifinals, reaching the title match for the eighth time in 11 appearances at the season-ending championships.

The Swiss will look to become the first player to win three straight titles since Ivan Lendl in 1987. Federer leads Djokovic 16-12 in their head to head series.

Murray, the US Open champion and Olympic gold medalist, has now lost in the semifinals on three occasions.

"I love playing against Novak," Federer said of the final on Monday. "He's had a great year and a great tournament so far. Facing off against Novak obviously is always special, especially at the World Tour Finals."