How Isner qualified
Back in 2015, John Isner was an alternate at the ATP Finals. Three years later, it looked like Isner would once again be an alternate after finishing the year at No 10. However, the 33-year-old becomes the oldest-ever debutant since 1972, after Juan Martin del Potro and Rafael Nadal withdrew through injuries. 2018 was by far Isner's best-ever year as he made it to his first Grand Slam semi-final at Wimbledon and followed it up with a quarter-final appearance at the US Open. The North Carolina native became the oldest first-time Masters champion after winning the Miami Masters. He beat a trio of top 10 players in Marin Cilic, Del Potro and Alexander Zverev to win the title at Miami.
Best performance of the season
Isner's mammoth Wimbledon semi-final against Kevin Anderson is probably the match of the year so far. Eyeing a first Wimbledon final spot, the duo played the second-longest match ever. The pair battled on Centre Court for six hours and 36 minutes before Anderson finally won the fifth set 26-24.
Isner's 2018 in a tweet
John Isner, through the 2018 French Open: 1 major quarterfinal in 40 major-tournament appearances
- Matt Zemek (@mzemek) September 2, 2018
Isner always bounces the ball between his legs before serving, something he says he picked up during his time playing basketball as a kid.
Head to head record against group players
John Isner 3 vs 7 Marin Cilic
John Isner 2 vs 8 Novak Djokovic
John Isner 1 vs 4 Alexander Zverev
For the rest of the profiles of contenders at the ATP Finals 2018, click here.