#4 Roger Federer vs David Nalbandian - 2005
David Nalbandian produced one of the best ever comebacks to defeat Roger Federer in the final in 2005.
Nalbandian had lost to Federer in the round-robin stage and was looking to avenge his defeat.
The final was a 5 set encounter and Federer won the first two sets. However, Nalbandian fought back to win the third and the fourth, during which Federer had called for the trainer as well.
Federer was serving for the match in the fifth but was broken despite being 30-0 up. Nalbandian then went on to win the tie-break and his first ever Tour Finals.
Result: Nalbandian d. Federer 6-7, 6-7, 6-2, 6-1, 7-6.
#3 Andy Murray vs Milos Raonic - 2016
Andy Murray, who was bidding for the World No 1 crown, had an extremely stern fight against Milos Raonic in the semifinal in 2016.
Clocking in at 3 hours and 38 minutes, the two players played the longest ever match in Finals history.
The Scot lost the first set 5-7 but clawed his way back to win the second and third sets in the tie-break. He went on to defeat Djokovic in the final to win his first ever Tour Finals and get crowned the World No 1 as well.
Result: Murray d. Raonic 5-7, 7-6, 7-6
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