PARIS -- John Isner has urged tennis authorities to resist revising the tournament calendar after Rafael Nadal's knee injury became the latest problem to curtail the playing time of the Big Four.
The Spaniard withdrew from the Paris Masters on Friday, and Roger Federer, Novak Djokovic and Andy Murray -- all missing from the tournament -- have also been sidelined by injury during the season. Of the Big Four, only Federer seems certain to take his place at the ATP Finals in London later this month.
Paris semifinalist Isner would qualify for London if he went on to win what is the last Masters event of the year. He told ESPN, "The season is manageable. I know a lot of players talk about the season being too long, but I don't think that.
"With Rafa, that's understandable. He's played more than anyone this year and plays such a physical game. I don't know what he would say, but I don't think the season is too long. You just have to be professional and try to go about your business.
"If you do it right, take care of yourself and have some luck, there is no reason you can't be playing at 100 percent at this tournament at the end of the season."
Floridian Isner called the trainer on twice as he beat Juan Martin del Potro 6-4, 6-7 (5), 6-4 in the quarterfinals Friday, but he insisted he is fit to face Serbia's Filip Krajinovic -- who progressed thanks to Nadal's withdrawal --- on Saturday.
The American celebrated with a cheeseburger and set his sights on the ATP Finals. "It would be a very big deal if I qualified," Isner said. "I didn't actually know I was mathematically alive coming into this event and found out a couple of days ago."
Isner had been looking forward to going home to watch some football later this month, but would be proud if he had to stay in Europe instead.
The 32-year-old, beaten by Murray in last year's final here, said: "I have never won a Masters event, I've never qualified for London either, and I've been on Tour for 10 years. But I've been close. This is my eighth consecutive year in the top 20 in the world and I'm pretty proud of that."