INDIAN WELLS, CA, USA – And then there were four. The BNP Paribas Open draw has dwindled down to a quartet of elite talents, including two former champions. Wtatennis.com breaks down a blockbuster semifinal day here.

Friday, Semifinals

Stadium 1
[1] Serena Williams (USA #1) vs. [3] Agnieszka Radwanska (POL #3)
Head-to-head: Williams leads 9-0
Key Stat: Williams has won 18 of 19 sets against Radwanska.
Will Serena Williams make it a perfect 10-0 against Agnieszka Radwanska on Friday to claim her spot in her first BNP Paribas Open final in fifteen years? If the scintillating form the two-time BNP Paribas Open champion displayed in her quarterfinal victory over Simona Halep is any indication, the American will be an extremely tough player to knock out of this draw. “She was moving really good, and hit it so strong,” an impressed Halep said after falling on Wednesday night to Williams. “I think she’s in good shape now. Yeah, maybe she’s going to win this title.”

In order to stop Williams from winning it all, Agnieszka Radwanska will likely have to play the match of her career. But if there was ever a time for Radwanska to pull a jaw-dropping upset, it could be now. The Pole has been the WTA’s most consistent performer since the US Open, going 34-6 with four titles, including the biggest of her career at last October’s BNP Paribas WTA Finals Singapore presented by SC Global. The momentum has certainly been building for Radwanska, but how to take that extra step to get past the daunting Williams? When they met two months ago at the Australian Open semifinals, Radwanska got off on the wrong foot and never recovered. “I think she started unbelievable, with such a power and speed,” she said at the time. “I was just standing there kind of watching her playing.” To avoid a similar situation Radwanska will have to make a high percentage of first serves and do everything in her power to stay in rallies and keep Williams off balance.

Williams is well aware that Radwanska is a threat, particularly on the gritty hard courts here in the desert, despite the lopsided victory in Australia and the 9-0 lifetime advantage. “Obviously she does everything so well, including running, and this is a good surface for her because it’s a slow surface,” Williams said. “I expect there will be a lot of long rallies. I will be ready.”

Pick: Williams in three

[13] Victoria Azarenka (BLR #15) vs. [18] Karolina Pliskova (CZE #19)
Head-to-head: series tied 1-1
Key Stat: Azarenka will return to the Top 10 (at No.8) for the first time since August 2014 if she wins the title at Indian Wells.
Victoria Azarenka reached only one WTA final in 2015, but the Belarusian is closing in on her second title of 2016 and we’re not even through March yet. It has happened in fits and starts over the last two years, but could we finally be witnessing the return to elite status of one of the WTA’s most talented — and decorated — players? Whether she reaches the final or not, one thing is certain: Azarenka is relishing the opportunity to prove herself on the big stage. “I love pressure,” she told reporters this week at Indian Wells. “That’s what makes me a good player and a great player. That’s what motivates me. Without pressure I get bored and it’s not fun. So to be able to compete in that high situation, that’s what I’m always looking forward to.”

Azarenka may be fine with the pressure, but how will the 2012 BNP Paribas Open champion handle the searing heat of Karolina Pliskova’s world-class serve? The tall, cool Czech ripped nine aces and won 24 of 26 first-serve points to take down Russia’s Daria Kasatkina on Thursday. How well Pliskova can dictate with her heavy offerings will be the key to her survival in this intriguing matchup, but in Azarenka she’ll be facing one of the WTA’s elite returners.

Pick: Azarenka in two

– Chris Oddo, wtatennis.com contributor