World No. 1 Novak Djokovic survived an early scare from Juan Martin del Potro inside of London's O2 Arena on Sunday, escaping his semifinal match with the Argentine in three sets, 4-6, 6-3, 6-2.
The Serb's win did not come easy though. Djokovic found himself down one set and down a break in the second before he snapped out of his funk and ultimately steamrolled del Potro in the final set.
The victory sends Djokovic through to the ATP World Tour Finals singles final on Monday, where he will face either the tournament's two-time defending champion, Roger Federer, or Andy Murray, whom he defeated in a three-set thriller earlier in the week.
For del Potro, the stinging loss means that he will leave London empty-handed despite earning an impressive win over Federer in the Group Stage.
What It Means
Djokovic's win means that he'll advance to Monday's final to take on the winner of Sunday's second semifinal match between Roger Federer and Andy Murray.
The 2008 ATP World Tour Finals singles champion, Djokovic, hasn't had much success against Federer in recent outings. The Swiss legend took him out at Wimbledon last summer and three months ago in the final at the ATP Western and Southern Open in Cincinnati.
On the other hand, Djokovic has defeated Murray as recently as Wednesday, when the two squared off in a Group A showdown.
Djokovic is one win away from a sixth singles title this year and is already assured to finish the season as the world No. 1 on the men's side for the second straight year.
A win on Monday would be but icing on the cake for the 25-year-old superstar. He has added another Grand Slam title to his name in 2012 and already done enough to warrant the world No. 1 label. All that's left to do is win a second ATP World Tour Finals competition and gear up for another spectacular run in 2013.
Follow Bleacher Report Featured Columnist Patrick Clarke on Twitter.