Four remain in the 2019 US Open Men's Semifinals. Two of the semifinalists come from the top five seeds in the tournament; one was seeded 24th, and one was an unseeded qualifier who has made it all the way through the first five rounds. Grigor Dimitrov powered through Roger Federer in their quarterfinal match on Tuesday, advancing in a grueling, five-set match that saw Dimitrov win the last two, 3-6, 6-4, 3-6, 6-4, 6-2.