It’s semifinal time on Thursday in Miami. We preview both of today’s must-see matchups at wtatennis.com.

Thursday

Semifinals

[10] Johanna Konta (GBR #11) vs. [11] Venus Williams (USA #12)
Head-to-head: Konta leads, 2-1
Key Stat: Konta became the first British woman to reach the Miami semifinals with her win over Simona Halep on Wednesday.

The last time Venus Williams and Johanna Konta locked horns it was an historic day for the British No.1. Konta claimed a three-set victory over the legendary American last summer to claim her first career title and become the first British woman to win the Bank of the West Classic title since 1977. Afterwards Konta summed up the experience aptly. “I wanted to leave it all out there, but also absorb everything that I could possibly reinvest in my career moving forward,” she said. “I’ve played her twice before and knew I’d be playing a magnitude of experience. Venus Williams doesn’t need an introduction.”

Williams and Konta split 144 points evenly in that entertaining final, but in the midst of her breakout season it was Konta who won the bigger points. Their fourth career battle should be similarly close, and if Williams’ form in her last two matches is any indication, she’s going to aggressively attack Konta and look to get to net often. The American became the oldest player to take out a reigning No.1 in WTA history on Wednesday night when she worked her way past Angelique Kerber, 7-5, 6-3, and while it’s easy—and inspiring—to focus on the fact that Williams is 36, the caliber of tennis she is playing belies her age. The three-time Miami Open champion has played brilliantly to reach the semifinals here for the eighth time, not dropping a single set and knocking off back-to-back Top 10 opponents in the process.

Will Williams take it a step further and avenge her loss in Stanford to Konta? The American will have her chances, but she’ll have to improve on her 45 percent first-serve percentage from her quarterfinal win over Kerber to do so. Konta picked apart Halep’s second-serve on Wednesday in her three-set victory over the Romanian, and Williams will need to keep the Dangerous 25-year-old on the back foot as much as she can to succeed.

Pick: Konta in three

[2] Karolina Pliskova (CZE #3) vs. [12] Caroline Wozniacki (DEN #14)
Head-to-head: Wozniacki leads, 3-1
Key Stat: Pliskova leads the WTA with 23 wins in 2017

They are very different stylistically, but Karolina Pliskova and Caroline Wozniacki share the same sinister approach to tennis warfare. Both are calm, composed and ruthless—eager to expose their opponent’s liabilities and unflappable under duress. That’s why Thursday’s matchup between the No.2-seeded Czech and the No.12-seeded Dane is so intriguing. The experienced, wily and extremely well-rounded Wozniacki will look to keep the powerful, blossoming Pliskova at bay, and she knows she’ll have to pull out all the stops to do it.

“She beat me last time we played, so she’s clearly in good shape,” Wozniacki said on Tuesday after defeating Lucie Safarova for her 22^nd win of the season. “I’m looking forward to getting another try, to see if I can beat her this time.”

Wozniacki won the first three times she faced Pliskova, but the Czech hit back earlier this season breaking Wozniacki’s serve four times in a 6-3, 6-4 win at this year’s Doha final. Despite that loss, Wozniacki is pretty confident that she has a good read on the towering Czech’s game. “I know her game, what her strengths and weaknesses are,” Wozniacki told reporters on Tuesday after her quarterfinal win.

Like Wozniacki, Pliskova has yet to drop a set this week in Miami. But she knows things will get tougher as the stakes get higher. “Anything can happen in the next semi,” she told reporters on Tuesday. “I would expect a tough one because I know she has been playing quite good here in last few years. … It’s the last tournament on hard court, so I just want to enjoy it.”

Pick: Pliskova in two

By the Numbers

7-1 – Konta’s lifetime record at Miami. She reached the quarterfinals on her debut last year.

2 – Pliskova is the only player left in the draw that has won multiple titles this season.

22 – Wozniacki has dropped just 22 games in her four matches en route to the semis. Pliskova, who has also yet to drop a set, has lost 24 games. Williams has dropped 27 games, and also not dropped a set.

14 – Number of wins that Williams has notched over reigning World No.1 players, including her win over Angelique Kerber in the quarterfinals.

49 – Number of career titles for Venus Williams, which is 14 more than the other three semifinalists’ career titles combined (Wozniacki, 25, Pliskova, 8, Konta, 2).