Juan Martin Del Potro may have been below his best in his win over Richard Gasquet, says Greg Rusedski, but his self-belief could take him far at the ATP World Tour Finals.
The Argentine prevailed 6-7 6-3 7-5 and Sky Sports pundit Rusedski reckons the world number five will take confidence from edging the two-hour, 23-minute contest.
"There was a bit of a Freudian slip in Del Potro's interview after the match," said said the former British number one.
"He said: 'I played solid, I didn't play great today but I got the job done'. But then he said: 'I hope I beat them a bit easier when I play Roger Federer and Novak Djokovic'.
"So he's confident, he believes he's only going to go up in this tournament and he believes he can go the distance this year.
"That's a good sign from Del Potro."
However, Annabel Croft says the 2009 US Open champion will have to raise his game when he meets Federer and Djokovic - two men who have won eight of the past 10 ATP World Tour Finals between them - in his other Group B matches.
Specifically, Croft feels Del Potro needs to examine his serve, despite a 79 per cent win-rate on his first serve points against Gasquet.
"He's had an absolutely fantastic season out there but surprisingly he didn't seem to serve that well tonight," she said of Del Potro.
"You expect him to get the free points and his game flows behind that big serve but Gasquet served more aces than Del Potro.
"I'm sure we'll see him out on the practice court trying to get that level up because a lot does depend on that."
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