Novak’s not going to miss,” the commentators in the booth at Roland Garros agreed.

Novak Djokovic and Stefanos Tsitsipas had reached the middle of the third set of their semifinal at Roland Garros, and there was little reason to doubt this assertion. To that point, Djokovic, the world No. 1 and top seed, had done what world No. 1s and top seeds tend to do. He had won the first two sets, over Stefanos Tsitsipas, 6-3, 6-2. He had defused an in-form opponent by blending deep groundstrokes with brutally well-measured drop shots. He had kept Tsitsipas, who had attacked his way to the semifinals, boxed in behind the baseline—when he wasn’t desperately sprinting to the net. Most important, Djokovic had won the points that mattered. Through two and a half sets, he had saved all 10 break points he had faced and converted on three of the four break-point chances he had earned.

Djokovic, it seemed clear, wanted to get this match over with as quickly as he could, and start preparing for the expected epic collision to come on Sunday, against Rafael Nadal. As expected, Djokovic broke Tsitsipas at 4-4 in the third, just in time for him to serve for the match. A 5-4, Djokovic proceeded to match point, lined up one of his favorite shots, a down the line backhand, and…sent it wide by about a foot.

No one knew, or probably suspected, it at the time, but the match was about to turn around completely. Tsitsipas, with nothing left to lose, took advantage of Djokovic’s miss by breaking serve for the first time all day. A few minutes later, he broke again to win the set. Suddenly, Tsitsipas was energized and Djokovic was slump-shouldered; Tsitsipas was the one moving forward and winning points with his own brutally well-measured drop shots; and Tsitsipas was the one saving break points, 11 of them in total, and converting on his own. After three hours, the match was, inexplicably, all even

Unlike many other all-time greats, who tend to be laser-focused, Djokovic has always had his phases, his ups and downs, his lulls and freak-outs. Even when he wants to get off the court in a hurry, best-of-five is a long time for this volatile personality to keep calm and carry on, and there’s often an eruption or two along the way. While he didn’t lose his grip on his emotions today, he did lose his grip on the match.

But best-of-five also gives Djokovic time to recover his equilibrium and reassert himself—he was 215-1 after leading by two sets coming into this match. And as quickly as it had turned against him in the third set, that’s how quickly he turned it back around in the fifth. He won going away, 6-3, 6-2, 5-7, 4-6, 6-1, in three hours and 54 minutes.

“I was definitely not pleased with the way I played the finishing stages of the third and fourth set,” Djokovic said. “But I was very pleased with the way I kept my composure mentally throughout the entire match.

“I did feel that even though I lost the third and fourth, I still felt like I was the better player on the court. I had more control. I just felt comfortable playing.”

Tsitsipas gave credit to Djokovic the “incredible athlete,” but he also blamed himself for trying to debut a new set of tactics, which he had been working on in practice, in a Grand Slam semifinal.

“I wish I wouldn’t have tried these things and tried to stay to my ordinary and basic way of feeling the ball and also trying to dictate the game,” Tsitsipas said. “I think that was a huge mistake today, that I tried this for two sets in a row, then came back to my old way of doing things.”

Tsitsipas didn’t elaborate on those new tactics, but there was no question that he let a few opportunities early in the match slip when he didn’t press forward aggressively enough. And the earlier he took the ball, and the more he moved in, the better he did in sets three and four. But it was always an uphill fight against Djokovic. The Serb was stronger with his serve, with his return, with his crosscourt backhand, and with his drop shot. Using the dropper so much paid off in the end, when Tsitsipas, who played a week of tennis in Hamburg before Roland Garros began, finally ran out of gas in the fifth set.

While Tsitsipas walks away after a valiant effort, and his trip to a first Roland Garros semifinal, Djokovic moves on to his 56th meeting with his Nadal, and their third in a final in Paris. Nadal won his semifinal in straight sets, while Djokovic took the long way home. He has had his costly struggles in French Open semifinals before—last year he lost in five sets to Dominic Thiem, and in 2015 he had to win a two-day affair with Andy Murray, which hurt him in his loss to Stan Wawrinka the following day.

Compared to those two years, he’s in good fairly shape this time around. Djokovic might not be the favorite against Nadal on Sunday, but would you count him out?