Juan Martin del Potro staged the comeback of the tournament in the match of the tournament on Day 8 of the 2017 US Open, coming back from two sets down to upset No. 6 seed Dominic Thiem in a packed, raucous Grandstand.

The first two sets took just over an hour, with Thiem surrendering just three games. The buzz surrounding the encounter centered more on if del Potro, ailing from a virus, would retire than if he could come back. But then he did, seemingly flipping a switch and stunning an unsuspecting Thiem to take the third set with ease.

Then the match really got going.

Del Potro broke early in the fourth set; Thiem immediately broke back. Then the No. 6 seed broke again, pulling ahead 5-2 and pushing the Argentine to the brink. But with his opponent serving for the match, the 6-foot-7 del Potro stood tall, breaking again to keep the match going. Undaunted, Thiem secured two match points with del Potro serving at 5-6; the 2009 US Open champion erased both with aces. The tiebreak was one-way traffic, Delpo running out to a 6-1 lead and securing the set with a cannonball of a forehand that is sure to be among the hardest the US Open has ever seen hit – a resounding strike that sent the standing-room only crowd into a state of utter delirium.

Then everyone took a deep breath, and the fifth set began. It did not disappoint. Thiem brushed away triple break point at 3-2, bottling a crowd that was ready to erupt. But in the end, he was only delaying what seemed like the inevitable. At 5-4, on del Potro’s second match point, Thiem spun a second serve that was called an ace. Del Potro challenged; the ball was wide. The match was over, Thiem leaving the court and the stage to his opponent, who raised his arms to the sky as the crowd showered him in cheers.

play video Del Potro vs. Thiem