MELBOURNE — For the second time in the tournament, Simona Halep faced match points and knew one mistake would mean an exit from the Australian Open and the likely loss of her No. 1 ranking.
For the second time in just over a week, she attacked rather than take the safe approach. The 26-year-old Romanian saved two match points and needed four of her own against 2016 champion Angelique Kerber before winning, 6-3, 4-6, 9-7, in the semifinals.
Halep will face No. 2 Caroline Wozniacki in the final on Saturday, with one of them guaranteed to win a first Grand Slam title. The winner will also be No. 1 when the next rankings are released. Wozniacki, who beat Elise Mertens, 6-3, 7-6 (7-2), in 1½ hours in the first semifinal, hasn’t held the top ranking in six years.
For Halep, playing in her first Grand Slam as the top-seeded player, it’s a first major final beyond the clay courts of Roland Garros. She lost the French Open final to Jelena Ostapenko last year — having led by a set and a break — and to Maria Sharapova in 2014.
For Wozniacki, it’s her first Grand Slam final outside of America. The two-time US Open runner-up also had to save match points to reach her first Australian Open final. She rallied from 5-1 down in the third set of her second-round win and said she’s been ‘‘playing with the house money’’ ever since.
Previous Australian Open winners have saved match points en route to the final, but no woman has done it in two matches.
Halep is hoping to change that, saying that saving triple match point in her third-round win against Lauren Davis that finished 15-13 in the third set had set her up mentally for the pressure of the semifinals.
‘‘Definitely was very tough. I’m shaking now, I’m really emotional because I could win this match,’’ Halep said immediately after beating Kerber in another marathon. ‘‘I’m glad I could resist. Not easy in the tournament to have these matches, but I have just to enjoy.’’
Marin Cilic is also enjoying his run, following up his quarterfinal upset against top-ranked Rafael Nadal with a 6-2, 7-6 (7-4), 6-2 win over No. 49 Kyle Edmund. After reaching the Australian final in his 10th attempt, the 2014 US Open champion will face the winner of Friday’s semifinal match between defending champion Roger Federer and Hyeon Chung.
Halep twisted her left ankle in the first round, and said she’d made the decision then to risk it all at Melbourne Park and take a rest later.
‘‘This match I had two match balls and I lost them so I said that if she came back, I can do it. I had just confidence in myself,’’ she said.
Halep has a new resolve after back-to-back first-round exits previously at Melbourne Park.
She won a lot of the long, intense rallies against Kerber and hit 50 winners, which surprised even her. She raced to a 5-0 lead in the first set, and led 3-1 in the second, but didn’t wilt as Kerber came back.
‘‘I try to be very calm, but today I was like a roller coaster, up and down,’’ she said. ‘‘But I didn’t give up, not even a ball. I’m really proud of myself, actually.’’
Wozniacki squandered a match point in an Australian Open semifinal match against Li Na seven years ago, but held her composure this time around and converted her first match point in the tiebreaker.
It was that semifinal loss to Li that has haunted her most among her near-misses.