Roger Federer fought back to beat Tennys Sandgren 6-3 2-6 2-6 7-6(8) 6-3 to reach the Australian Open semifinals for the 15th time.
Federer who had the upper hand in the first set trailed behind in the next two sets but astonishingly saved seven match points to take the game into the fifth set to seal a classic victory.
Fans praised the 38-year-old for his resilience and show of mental strength despite suffering an injury and also getting a warning for “obscenity” from the Umpire.
He remains unbeaten (15-0) in quarter-finals at this event and will next face second-seeded Serbian Novak Djokovic or No. 32 seed Milos Raonic of Canada.
Federer trails Djokovic 23-26 in their rivalry and has lost their past three matches in Melbourne, all of which took place in the semi-finals (2008, 2011, 2016). The Swiss leads Raonic 11-3 in their series and won their lone clash at this event in 2013.