On the surface, Thursday’s Roland Garros semifinal encounters might appear to be mismatches. It’s the World No.1 and No.2 with that top spot very much in play, operating against vastly underrated, overlooked opponents.

But, as we have seen many times, appearances can sometimes be deceiving. Those head-to-heads might not be as one-sided as you think.

Beatriz Haddad Maia defeated Iga Swiatek in their only previous meeting.

French Open: Scores | Order of play | Draw

For Aryna Sabalenka, she needed the maximum 14 games to win in straight sets over Karolina Muchova the only time they met.

Swiatek and Sabalenka have already played twice recently in clay finals, with Swiatek winning in Stuttgart and Sabalenka reciprocating in Madrid. But before we contemplate a third with so much at stake, they each face a serious challenge.

Here’s what they’re looking at:

No.2 Aryna Sabalenka vs. Karolina Muchova

Now here is a wonderful contrast in styles.

The fierce Sabalenka -- the one with a tiger tattoo on her arm -- hits the ball about as hard as is humanly possible and, emotionally, wears her heart on her sleeve. While Muchova is blessed with an infinite variety in her game.

Karolina Muchova and a throwback to traditional tennis artistry

Fire versus ice -- how will it play out on Court Philippe Chatrier at 3 p.m. local time (9 a.m. ET)?

They played four years ago in China when they were very different players. Sabalenka was a 7-5, 7-6 (4) winner and it will take another, poised and concentrated effort to reach her first French Open final.

Muchova bests Pavlyuchenkova at Roland Garros

Sabalenka has been the most successful player on the Hologic WTA Tour this year. She’s already won 34 matches this year, one more than the 2022 season in which she reached the championship match of the WTA Finals. Moreover, she’s won all 12 of her Grand Slam matches to start the season, the first woman to do that since Serena Williams in 2015 and only the fifth to do it this century.

The quality, the weight of her shots, even on the red clay, has been eye-opening. And she has a decent chance to emerge from Paris with the No.1 ranking that Swiatek has hoarded for the past 62 straight weeks.

Sabalenka ends Svitolina's run to reach first French Open semifinal

And despite all of this, Muchova is uniquely equipped to pose problems. Sabalenka is a rhythm player and Muchova is a rhythm-wrecker, a human changeup. She can play big from the back, slice and dice, close at the net and hit a sensational drop shot -- whatever the circumstances require.

Her ranking coming in was No.43 and she drew No.8 seed Maria Sakkari in the first round. All Muchova did was win in straight sets, something she’s accomplished in four of five matches.

And figuratively speaking, she’s been here before. This is her second career major semifinal, going back to the 2021 Australian Open. She almost sounded excited to play Sabalenka.

“What can I say?” Muchova said. “She’s very, very great player. Very aggressive. Tough match ahead. I’ll try to do my best to find a way how to make it complicated for her.”

No.1 Iga Swiatek vs. No.14 Beatriz Haddad Maia

The superlatives are, quite frankly, increasingly difficult to grasp.

Swiatek has won 26 of 28 matches at Roland Garros; that winning percentage (92.9) is second only to Margaret Court at the Australian Open (95.5) and French Open (95.2) among all other women in the Open Era.

The 22-year-old Swiatek has dropped all of 15 games in five matches, meaning only people named Pierce, Graf, Martinez and Navratilova have arrived in this final four with fewer losses in the Open Era.

Swiatek took care of Coco Gauff for the seventh time in seven tries, 6-4, 6-2. Ultimately, the 19-year-old had no answers; Swiatek saved four of five break points against her, while Gauff saved one of five.

This is the second semifinal, scheduled for around 5 p.m. local time (11 a.m. ET).

What to make of the unlikely, unfolding story that is Haddad Maia? How did the 27-year-old Brazilian -- who had never been past the second round of a Grand Slam -- reach the final four in Paris?

Haddad Maia came back for the third straight time to win a three-set thriller, this time besting No.7 seed Ons Jabeur 3-6, 7-6 (5), 6-1. It was her first time playing on Chatrier and first win against a Top 10 player in a major. The tenacious left-hander is the first woman in the Open Era to advance to the Roland Garros semifinals with three-set comebacks in the three previous rounds.

“For sure, she’s the fighter, and she showed even today,” Swiatek said. “Fighting until the last ball -- it pays off. You have to kind of be ready even when you feel like you’re leading or whatever. You have to play every point 100 percent.”

Six weeks ago in Stuttgart, Jabeur dropped only three games in a little over an hour’s time in their first career meeting. After playing the longest match this year on the WTA Tour (3 hours, 51 minutes), Haddad Maia completed this upset in a relatively scant 2 hours, 31 minutes.

Here’s a statistic that underlines that ability to remain unflappable in big moments: Only Elena Rybakina (nine) has won more tiebreaks this year than Haddad Maia’s eight. And while the Brazilian has spent far more time on court than Swiatek, at 775 minutes to 332, it’s worth revisiting the one match they’ve played.

A year ago, Haddad Maia sliced through the Toronto field in memorable fashion, defeating Canada’s own Leylah Fernandez before getting Swiatek in the fourth round. It was Haddad Maia’s first opportunity against a No.1 player, and she didn’t flinch. Converting her fourth match point, Haddad came back to win a 3-hour match, 4-6, 6-3, 7-5. She went on to beat Belinda Bencic and Karolina Pliskova on the way to the final where she fell to Simona Halep.

“A tennis match is like a marathon,” Haddad Maia told reporters afterward. “It’s not 100 meters race. I think one of my qualities is that I wait and I’m very patient. I never give up, so I wait for the moment because I know that my level is high.”