ATP Finals: John Isner profile
American John Isner only found out last week that he would be playing at the ATP Finals in London after world number two Rafael Nadal withdrew through injury.
The 33-year-old will be aiming to add to the two titles he has won this year.
His opponents in the Guga Kuerten group for the round-robin stage are Novak Djokovic, Marin Cilic and Alexander Zverev.
He starts his campaign against Djokovic on Monday (not before 20:00 GMT).
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