Dominic Thiem beats Gael Monfils at ATP World Tour Finals

Thiem took a hard-fought first set thanks to a far-superior serve unleashed against an opponent who did not look at his best.

In fact, the crowd at the O2 would have been forgiven for preparing for an early exit as Monfils limped around and struggled to live up to his usual athleticism on the court.

However, an inspired Monfils made a stunning comeback in the second set, dropping hardly any points on his serve and outclassing Thiem.

With the players level-pegging in the third and final set, the Frenchman lost his nerve in the final game of the third set, hitting a string of double faults to give the Austrian a way back into the match.

A valiant effort by Monfils was alas to no avail as the Austrian capitalised on Monfils' demise, to record his first win at an ATP Tour Final. His final game in the round-robin will be against Milos Raonic, while Monfils has the unenviable task of taking on Novak Djokovic to see if he can leave the tournament with any wins to his name.