Alex de Minaur has progressed to the third round of the ATP Masters 1000 event in Indian Wells with a straight-sets victory over countryman Aleksandar Vukic.

De Minaur was the only Australian winner on the day in the California desert after John Millman was easily dispatched by 10th-seeded Jannik Sinner.

Vukic had come through qualifying and a first-round assignment but could not overcome the consistency of the 22nd-seeded de Minaur who secured a 6-4 7-5 result.

De Minaur broke serve four times while saving five of seven break-point opportunities Vukic created to close out the match in one hour and 35 minutes and set up a round of 32 encounter with Cristian Garin, the Chilean ninth seed.

Millman was up against it in his first career meeting with Sinner, who cruised to a 6-2 6-2 victory with breaks of serve in the third and seventh games of each set.

The 20-year-old Sinner was dominant on serve as he won 86 per cent (18/21) of first-serve points and 74 per cent (14/19) of second-serve points.

"Today, I played very well. I didn't miss many shots and I felt great on court," Sinner said.

"I had one week of practice here so it was quite long to prepare, which is very good."

Sinner was not the only Italian through to the round of 32 with world No.7 Matteo Berrettini defeating Chilean Alejandro Tabilo 6-4 7-5 and Fabio Fognini getting past Jan-Lennard Struff 6-4 4-6 6-3.

Third-seeded German Alexander Zverev overcame second set errors to defeat American Jenson Brooksby 6-4 3-6 6-1, launching a dozen aces - including 10 in the third set alone - in his bid for a third Masters 1000 title this year.

Andy Murray battled past Spanish teenage sensation Carlos Alcaraz - who he has tipped as a future world No.1 - 5-7 6-3 6-2 in a battle that lasted more then three hours.

Alcaraz, 18, who reached the quarter-finals of this year's US Open, initially looked awestruck by the occasion as a string of unforced errors left him trailing 3-0 and 0-40 at the start of the match.

But from the verge of a double-break down he grew in confidence, and took the first set before Murray's experience and versatility - including an audacious under-arm ace straight from the Nick Kyrgios textbook - won out.

Stefanos Tsitsipas stormed into the third round at Indian Wells for the first time as the second seed beat Spaniard Pedro Martinez 6-2 6-4 under lights to set up a clash with Fognini.

The Greek broke serve to take a 2-0 lead in the opening set which he claimed with ease, but he was made to work much harder in the next set by his unseeded opponent.

World No.61 Martinez, who lost the pair's only previous meeting in straight sets at Roland Garros earlier this year, was determined to push Tsitsipas all the way as he raced ahead 3-1 in the second set with an early break.

But French Open runner-up Tsitsipas quickly found his rhythm again to claw his way back and close out the contest in style.

Among the others to reach the round of 32 were Gael Monfils, Pablo Carreno Busta and Albert Ramos Vinolas, who eliminated seventh-seeded Felix Auger-Aliassime.