Victoria Azarenka booked her spot in the Indian Wells Open semi-finals after a straight-sets victory over Jessica Pegula.

Azarenka – a two-time Indian Wells champion in 2012 and 2016 – accounted for Pegula at the WTA Premier 1000 event in the desert on Wednesday.

The former world number one will play 2017 French Open winner Jelena Ostapenko in the semi-finals after she got past American Shelby Rogers.

AZARENKA FLEXES TO BOOK SEMI-FINAL SPOT

Two-time Australian Open champion Azarenka won 6-4 6-2 over Pegula, who had beaten fourth seed Elina Svitolina in the fourth round.

Pegula hit 27 winners compared to Azarenka's 21 but the American had 30 unforced errors, with her 27th-seeded opponent also winning 81 per cent of first-service points to claim the edge.

"I started going for my shots from the beginning. I knew I have to apply pressure on her," Azarenka told her post-match news conference.

"I will have the moment where I will have opportunity. I think in the beginning of the match we had a lot of great rallies, a lot of points where I was like, 'Oh, maybe I got this one,' and she got me. I felt that I really just stuck to being aggressive and being consistent. I got my opportunities."

She added: "I felt that I really played well in the crucial moments. I felt like I stepped up a lot to the occasion. That's what I'm really happy with today."

OSTAPENKO FINISHES STRONG OVER ROGERS

Ostapenko earned her final-four spot with a see-sawing 6-4 4-6 6-3 win in two hours, 15 minutes over Rogers.

In a match that included 15 breaks of serve, Ostapenko won the final five games as she rallied to secure victory and her third semi-final of the year.

"I'm really happy to be in the semi-final. It's been a tough year for me, I've been up and down," Ostapenko – the 24th seed – said during her on-court interview. "I feel like my tennis is getting better and more consistent. Today I was trailing 3-1 in the third set and I was fighting to the last point."

Former world number five Ostapenko trailed 3-1 in the final set before finishing strong to set up a showdown with Azarenka. 

"She's a great player, great champion, such a fighter," Ostapenko said about Azarenka. "Hopefully I can just enjoy it."