Barbora Krejcikova vs. Maria Sakkari was tennis at its dramatic best.

So you think you’ve just won your first Grand Slam semifinal. You’ve watched a ground stroke from your opponent land near the baseline, and heard the line judge call it out. You’ve thrown your hands into the air. Then you’ve stood in horror as the chair umpire walked over, stared at the mark, reversed the call, and told you to replay the point.

How do you regroup from that and win a match of this magnitude, when you think it already should be yours.

Barbora Krejcikova can tell you. In a nerve-filled epic against Maria Sakkari at Roland Garros on Thursday, she had come back from 3-5 down in the third set to lead 8-7. She had saved a match point, and lost three of her own. She had celebrated the biggest victory of her career, only to have it snatched back from her by the umpire.

“At that moment I was just like, ‘Well, it’s out, but what can you do?’” Krejcikova said. “The chair umpire, he has seen it as in. What can I do? I cannot do anything about it. I cannot call anyone, change his decision.

I was like, ‘OK, well... it’s fine. Doesn’t matter. Just let’s go.’”

“You just have to put everything together and just keep working, next one, next one, next one.”

Unofficial Hawk-Eye replays on TV agreed with Krejcikova that the ball was out. Should this be the match that finally forces Roland Garros to start employing the replay technology, and stop relying on ball marks? I’ll start by saying that the version of Hawk-Eye used for television may not be as extensive, and thus not as accurate, as the one used for matches, so we probably shouldn’t make a wholesale change based on this call alone. I do think the tournament should use Hawk-eye; even if it has a margin of error, it’s surely more reliable than the umpires’ after-the-fact interpretations of where a ball landed. But if Roland Garros doesn’t want to to make that change, TV networks should stop showing less-than-accurate replays.

But that’s a discussion for another day, or year. Today center stage belonged to the Czech and the Greek. Neither had played a major singles semifinal before, and it showed. Over three hours and 18 minutes, they grabbed leads and gave them back, played brilliantly for stretches and poorly for others, overhit on some big points and were too tentative on others. Together they made 111 unforced errors and hit 58 winners, and had more double faults than aces. But none of those numbers mattered. What mattered was how their nerves, and the courage they showed trying to overcome them, flowed from one side of the net to the other over the course of a long afternoon, as these two women tried to do something they had never done, and may never have believed they would do—reach a Grand Slam singles final.

“I actually think we both deserve to win because we play really, really great match,” Krejcikova said. “But only one can win. I’m really happy that it’s me, that I’m going to have another chance to play another match. I think the match was really up and down. I just told myself, ‘Just fight, fight, fight until the last point. I’m happy that I was really fighting.”

The rallies, many of them long and complex, pitted Krejcikova’s smooth, varied shotmaking—she changed directions and spins constantly—against Sakkari’s hard, straight-ahead hitting. Personality-wise, it pitted Krejcikova’s expressionless calm against Sakkari’s fiery relentlessness.

The difference in the end was Sakkari’s inability to find the right mix of aggression and margin in the latter stages, when the match was on the line. Her game is to press and attack, but when she served for the match, she pressed a little too hard and made four errors. Then, with Krejcikova serving at 4-5, Sakkari went in the other direction and didn’t press hard enough.

“I have to be deadly honest,” Sakkari said. “I got stressed, started thinking that I’m a point away from being in the final. I guess it’s a rookie mistake…Got a little bit more passive on my game. Yeah, didn’t go for it. I just didn’t play offensive. I was a little bit defensive, especially in the big points. I couldn’t find a way to break her after five-all.

“I think it’s human emotions, but I think I’ll learn from it.”

And that’s what this anxious epic was about, and what all great matches are about: human emotions. Krejcikova-Sakkari was far from perfect, but it was tennis at its dramatic best.