John Isner (seed 8, ranking No 10)
Isner qualified for the season-ending event after Nadal’s last-minute withdrawal due to injury. Making his debut at the season-ending finale, the American will look to make it large in London. Having won two titles in the season, the 33-year-old can trouble the members of this group.
Isner might be the underdog in this tournament but he is coming off a brilliant season. The American won his first career Masters 1000 title in Miami and a hard court title in Atlanta this year. Isner also made a Grand Slam semifinal at Wimbledon where he played an epic five-setter against Kevin Anderson which almost sent shock waves against tennis fans. The deciding set almost went to 24-26 and the American had to taste a bitter defeat in a match that was so close.
It was heartening nevertheless to see Isner catch up after a slow start to the season and making it to the prestigious final eight.
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