For the third time in the past three seasons, Stan Wawrinka has done the toughest thing in tennis: stop Novak Djokovic in the latter stages of a Grand Slam tournament.

Sunday’s victory came in the United States Open final, and Wawrinka’s 6-7 (1), 6-4, 7-5, 6-3 triumph gave him a third major singles title, at age 31.

He has had to solve the riddle of the elastic Djokovic to win them all. Wawrinka surprised Djokovic in the quarterfinals en route to the 2014 Australian Open title; stunned him in the final to win the 2015 French Open; and has now beaten him in a final at Arthur Ashe Stadium.

At this stage, it is hard to call this one an upset, although Wawrinka certainly had to overcome plenty of shaky moments. In the third round, he saved a match point against the British outsider Dan Evans. Five minutes before he walked on court to play Djokovic, he broke down in tears while speaking to his coach, Magnus Norman.