Saturday's six semifinals on the ATP and WTA offer plenty star power, and even more intrigue.

Stefanos Tsitsipas vs. Jannik Sinner

Last weekend, after beating Andrey Rublev in the Monte Carlo final, Tsitsipas said that the future of men’s tennis wouldn’t be about any “singular” rivalry. It would contain multiple ongoing duels, involving upwards of 10 top players. As if to prove his point, on Saturday Tsitsipas will play his third straight match against a fellow Next Gen hopeful: On Thursday, he beat 22-year-old Alex de Minaur; on Friday, he beat 20-year-old Felix Auger-Aliassime, and now he’ll take on 19-year-old Jannik Sinner—who is coming off his own quarterfinal win over Rublev.

Tsitsipas and Sinner have already faced off twice on red clay, both times in Rome; the Greek won the first, the Italian took the second. Sinner, a finalist in Miami last month, is undoubtedly on the rise, but Tsitsipas’s confidence seems to be peaking at the moment. In his three straight-set wins in Barcelona, he has shown no signs of being weary or satisfied after winning his first Masters 1000 title in Monte Carlo. In this match-up, Tsitsipas has a little more variety—enough for a Plan B if Plan A doesn’t work—than Sinner does. Winner: Tsitsipas

Pre-match pressers:


Rafael Nadal vs. Pablo Carreño Busta

Nadal likes to play on clay, and he likes to play his fellow Spaniards. That combinations hasn’t served Carreño Busta well over the years. He’s 0-7 against Nadal, and hasn’t won a set in any of their matches on dirt. Plus, he’ll be coming off a late-night, three-set, war-of-attrition win over Diego Schwartzman in the quarterfinals on Friday.

Does Carreño Busta stand any chance? He did push Rafa to a third set on indoor hard courts at the Paris Masters last fall, and Nadal is still in the process of his finding his clay form this spring, having won two matches in three sets this week. Unfortunately for PCB, beating him for the eighth straight time will probably be one more step in that process. Winner: Nadal

Ash Barty vs. Elina Svitolina

Normally, when a player comes back from 3-5 down in the third set to win a match, the way Barty did against Karolina Pliskova in the quarterfinals, we’d say she’s playing with house money, and that she should be a little more relaxed in her next match. Except that in this case, Barty’s opponent, Svitolina, engineered an even bigger comeback in her own quarterfinal. Down a set and 5-2 to Petra Kvitova, Svitolina dug in and fought back to win in three. Which means it’s safe to say that both Barty and Svitolina should feel happy to be in the semis, and confident that they can bounce back from just about any deficit.

Who should feel the more confident of the two? You might think that their head-to-head would favor Svitolina, who leads it 5-2. But Barty has won their two most recent meetings, including one in the semifinals in Miami just a few weeks ago. You might think the surface, clay, would also favor Svitolina, who has won multiple events on it over the years. But Barty has won the biggest clay event, Roland Garros. So I’ll go with their rankings and take the world No. 1, in what should be a good one. Winner: Barty

Hot Shot: Elina Svitolina's backhand


Simona Halep vs. Aryna Sabalenka

It’s early in the clay swing, but this seems like a match that could have repercussions for the rest of it. Halep is 3-1 against Sabalenka, and the much more accomplished dirt-baller. That and the fact that Sabalenka comes into this match having survived a long, late, quarterfinal against Anett Kontaveit makes Halep the clear favorite. But Sabalenka is also someone who has begun to make herself a regular threat against the top players, and, for the first time, at the majors. A win over the world No. 3, and 2018 Roland Garros champion, would be a big statement as the WTA heads to Madrid, Rome, and Paris. If she’s not too tired, Sabalenka could make it. Winner: Sabalenka

Matteo Berrettini vs. Taro Daniel

Ranking-wise, this looks like a mismatch: Berrettini is 10th, Daniel is 126th. But Daniel won the only previous meeting between the two, on clay, in 2018. Daniel should also have built up a fair bit of momentum in Belgrade by now; a lucky loser, he’s 4-1 so far this week. Still, despite injuring himself earlier this year in Australia, Berrettini, who is a multi-surface threat, remains the favorite. Winner: Berrettini

Belgrade quarterfinal recap:

Novak Djokovic vs. Aslan Karatsev

When these two met for the first time at the Australian Open in February, Karatsev was ranked No. 114. Two short months later, the Russian is No. 28, has reached his third semifinal of 2021, and has made it feel as if he’s been in the ATP’s upper echelon for years. Now for the next challenge: Can Karatsev improve on his never-in-doubt, 6-3, 6-4, 6-2 loss to Djokovic in Melbourne?

He should feel more comfortable going out on court against the world No. 1 by now, and he shouldn’t feel as overwhelmed by the stage in Belgrade. The problem is, Djokovic may be just as motivated to win his newly-resuscitated home tournament as he was to win his ninth Aussie Open. Djokovic has won his first two matches in Belgrade 6-1, 6-3; can he make it three in a row? Winner: Djokovic


Joy of Six: Semifinal previews for Barcelona, Stuttgart and Belgrade

Joy of Six: Semifinal previews for Barcelona, Stuttgart and Belgrade