Taylor Fritz credits quality of his serve after winning start at ATP Finals

Fritz served 13 aces to Musetti's five, but their first serve percentage was pretty similar as the former was at 66 per cent while Musetti's was 65.

The crucial difference was points won when the first serve was in as the American was at 84 per cent (31 from 37) and the Italian's was at 40 (12/30).

During the post-match press conference, the world No 6 was asked if the outcome was decided by his excellent serve or Musetti's poor returns

Fritz told reporters: "I think it's more probably the quality of the serve. For me, I'm serving for, like, lines. I'm never serving to kind of put it in.

"I'd rather miss my serve than make it and it not be very good. I think I did a good job mixing up the serve. Yeah, I feel like I'm hitting the spots pretty good on the serve.

"To be honest, I think one of the things he's always done really well against me is neutralise my first serve. I think he's very good at chipping the return deep and putting it in positions where it's tough for me to attack.

"I wouldn't say it's his return because I think that's been one of the things that's made it tough for me to play him in the past, is how well he can typically return my first serve if the spot is not very good."

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