PARIS — The ball landing at Barbora Krejcikova's feet on match point appeared to come down behind the baseline.
The linesman thought so and called the shot long. A TV replay confirmed as much, and the unseeded Krejcikova was so sure that she raised her arms in triumph to celebrate a berth in her first Grand Slam final at the French Open.
Chair umpire Pierre Bacchi disagreed. He reversed the call, sparking a fresh round of debate about video replay and briefly delaying Krejcikova's victory.
Tennis was spared an unjust result five points later, when she hit a backhand winner to close out the biggest victory of her career. The 25-year-old from the Czech Republic saved a match point midway through the final set and outlasted No. 17-seeded Maria Sakkari of Greece, 7-5, 4-6, 9-7, on Thursday.
"I always wanted to play matches like this," Krejcikova said.
She must like roller coasters, too. Her opponent Saturday will be No. 31 Anastasia Pavlyuchenkova, a 29-year-old from Russia who also advanced to her first major final, doing so by beating unseeded Tamara Zidansek of Slovenia, 7-5, 6-3.
It was only the second time in the professional era that there were four first-time Grand Slam women semifinalists at a major tournament, and the first time since the 1978 Australian Open.
Krejcikova, a two-time major doubles champion ranked 33rd, is playing singles in the main draw of a major tournament for just the fifth time. Pavlyuchenkova, by contrast, has played in more majors before reaching a final (52) than any other woman. A top-20 player as a teen — she'll return to that segement of the rankings next week — Pavlyuchenkova had been 0-6 in major quarterfinals before finally clearing that hurdle Tuesday, and she was steadier than the big-swinging Zidansek in their semifinal.
"I wanted this so much that right now I don't feel anything," Pavlyuchenkova, who has 12 career WTA victories, told the crowd in French.
Krejcikova's run to the final is equally improbable.
"It sounds incredible," she said. "I cannot believe it. It's actually happening."
It seemed especially unlikely nine games into the third set, when Sakkari held a match point. She confessed she then became less aggressive.
"I got stressed, starting thinking that I'm a point away from being in the final," she said. "I guess it's a rookie mistake."
Krejcikova erased the match point with a swinging volley for a nervy winner, and 40 minutes later they were still playing.
Then came the real drama. With Krejcikova holding a match point in the final game, Sakkari hit a forehand near the baseline. Bacchi climbed off his chair, took a look, called the shot good and ordered the point replayed.
"He came and he's like, 'It's in,' and I'm like, 'No, no, no, no, no, no. Why?'" she said with a chuckle. "But what can I do? I cannot change his decision. It's fine; let's go. Let's try to just win the next one."
A TV replay indicated the ball was clearly long, but video review isn't used at Roland Garros, where the balls usually leave clear marks in the clay.
Krejcikova kept her cool and was celebrating for good moments later after converting her fifth match point.
Krejcikova is also bidding to become the first woman to win both the doubles and singles titles at the clay court major since Mary Pierce in 2000. She and Katerina Siniakova have advanced to the semifinals Friday.
There wasn't as much drama in the day's first match, but the quality of play was as enjoyable as the warm, cloudless weather. The 85th-ranked Zidansek, who this week became the first Slovenian woman to reach a Grand Slam quarterfinal, was the better player for much of the first set, moving well and hitting the more aggressive groundstrokes.
But Pavlyuchenkova won the most important points, and Zidansek dumped consecutive shaky serves into the net to lose the set.
Pavlyuchenkova's groundstrokes carried more sting in the second set as she raced to a 4-1 lead. Her first sign of nerves came as she double-faulted twice, including on break point, to make it 4-3, but she broke back and easily served out the victory.
"Tennis is such a mental sport," she said. "That's what is really hard about tennis."