PIX: No stopping Alcaraz, Andreescu at Miami Open!

Carlos Alcaraz swatted aside Serbian Dusan Lajovic 6-0, 7-6(5)to keep his title defense on track at the Miami Open on Sunday, as Canadian Bianca Andreescu cruised past American Sofia Kenin in straight sets.

Spain's teen phenom won Indian Wells to retake the top ranking last week and kept the momentum going at Hard Rock Stadium as he fired off 26 winners to set up a fourth-round meeting with Australian Open semi-finalist Tommy Paul.

"I always think that you have to go for it," he told the Tennis Channel after the match. "That's what I told myself in (those) tough moments."

Lajovic stunned three-times Grand Slam winner Andy Murray in the first round but never hit his stride on Sunday, letting his only break point chance slip through his fingers in the first set as the US Open winner put on a near-flawless performance.

Alcaraz converted on a break point in the third game of the second set with an expertly placed forehand winner but helped his opponent to a break in the 10th game with a handful of uncharacteristic errors.

Lajovic refused to go down without a fight, fending off three match points in the tiebreak. But Alcaraz never lost his nerve and clinched it with a blistering backhand winner before pumping his fist triumphantly.

"Everything was under control," said Alcaraz, who greeted the Miami Heat's six-time NBA All-Star Jimmy Butler courtside after the match.

"But end of match is never easy. The nerves came out. I made a few mistakes that I didn't do around the whole match. So it was tough to win."

Former US Open champion Andreescu harnessed her mighty serve to topple Kenin 6-4, 6-4, sending over seven aces as the 2020 Australian Open winner failed to mount much of a defense after an early exit from Indian Wells.

The swift affair was welcome reprieve for Andreescu after lengthy battles against first- and second-round opponents Emma Raducanu of Britain and World No 10, Greek Maria Sakkari, with Ekaterina Alexandrova waiting in the round of 16.

"I definitely enjoy the challenge," she said in a televised interview. "These victories are definitely very sweet and I've had many tough matches against Sofia."

Earlier on Sunday, Denmark's Holger Rune sent over seven aces and 27 winners to stop Argentine Diego Schwartzman 6-4, 6-2. The seventh seed next faces American Taylor Fritz for the first time in the fourth round.

Later on Sunday, second-seeded Australian Open champion Aryna Sabalenka plays 31st seed Marie Bouzkova and last year's twice Grand Slam runner-up Casper Ruud, seeded third, plays the Netherlands' Botic van de Zandschulp.