LONDON (AP) Dominic Thiem won his first match at the ATP finals, beating Gael Monfils 6-3, 1-6, 6-4 on Tuesday.
The eighth-seeded Austrian, who is making his debut at the season-ending tournament, could advance to the semifinals with a win over Milos Raonic on Thursday.
Second-ranked Novak Djokovic will face Raonic in the late match. Both won their opening matches, and Djokovic will advance if he wins.
Thiem struggled in the second set on Tuesday, just like he did in the loss to Djokovic on Sunday. But he improved his service game in the final set, winning 79 percent of the points on his first serve.
He was also able to break Monfils in the final game as the Frenchman produced three of his five double-faults in the decider.
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