The second set was much more even as both players held their serves to take the match into a tiebreak, where Anderson's serve once again gave him the edge, although Thiem played well enough to think he still has chances of reaching the semi-finals.

"It's just fantastic to be here," said 32-year-old Anderson, who was making his ATP finals debut.

"I've worked so hard to be here, I've been watching this tournament since I was a little kid so to come out here and play in such an amazing atmosphere and get the win is fantastic. I couldn't be happier right now," he commented.

Monday sees World Number 1, Novak Djokovic play his first match when he faces American, John Isner, while Alexander Zverev faces Marin Cilic.

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