Chung Hyeon’s historic Australian Open run came to an end in his semifinal match against Roger Federer on Jan. 26. Chung was forced to retire midway through the second set due to a massive blister on his foot, a photo of which he posted to his Instagram account following the match. Chung, who is nicknamed “The Professor” because of his trademark glasses, became the first Korean tennis player to advance to the semifinals of a Grand Slam event during the tournament. Following the match, Chung told reporters, “I enjoyed the past two weeks, on and off the court. I’m just really happy.”