#4 Kevin Anderson vs Roger Federer - Wimbledon Quarterfinals
On paper, Kevin Anderson defeating Roger Federer might not be a huge upset like the way the others on this list are. However, it was the occasion and the nature in which Anderson fought and won the match that was quite shocking.
Federer was two sets up to love and held a match point only to see Anderson produce one of the best ever comebacks to send Federer packing. And, what made it even more shocking for Federer and his fans was that it happened at Wimbledon!
Result: Kevin Anderson def. Roger Federer 2-6, 6-7(5), 7-5, 6-4, 13-11
#3 Marco Cecchinato vs Novak Djokovic - French Open Quarterfinals
Marco Cecchinato had never won a Grand Slam match before the French Open. Despite that, he became the first Italian man in 40 years to reach a Grand Slam semifinal. And in order to get there, he upset Novak Djokovic, who was still on his comeback trail, in four sets.
Cecchinato won the first two sets but Djokovic fought back in the third to win it 6-1. He was up 5-2 in the fourth set but lost his serve and then went on to lose the tie-breaker as well to send the stadium into shock.
Cecchinato qualified for the semis but went on to lose to Dominic Thiem.
Result: Marco Cecchinato def. Novak Djokovic 6-3, 7-6 (7/4), 1-6, 7-6 (13/11)
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