Jannik Sinner crushed Australia's Thanasi Kokkinakis 6-3 6-0 to reach the third round of Indian Wells and extend his winning streak this season to 13 matches.
The Australian Open champion will next face either 25th seed Jan-Lennard Struff or Croatian Borna Coric.
Elsewhere, Andy Murray fell to Andrey Rublev 7-6(3) 6-1. The Russian will meet Czech 32nd seed Jiri Lehecka in the third round.
Second seed Carlos Alcaraz overcame a sluggish start to dispatch Italy's Matteo Arnaldi 6-7(5) 6-0 6-1 to get his hopes of a title defence in the California desert off to a winning start.
Sixth seed Alexander Zverev and 11th seed Stefanos Tsitsipas both advanced in straight sets, while rising American Ben Shelton came from behind to score a 4-6 6-3 6-4 win over Czech Jakub Mensik in other second round action.
In the women's competition, world number one Iga Swiatek blasted past American Danielle Collins 6-3 6-0, Angelique Kerber upset 10th seed Jelena Ostapenko and defending champion Elena Rybakina withdrew with illness in second round action.
Kerber scored her biggest win in three years with an impressive 5-7 6-3 6-3 victory over hard-hitting Latvian Ostapenko.
In another upset, 22-year-old American Katie Volynets stunned sixth seed Ons Jabeur 6-4 6-4 and will face Caroline Wozniacki in the third round after the Dane outlasted Donna Vekic 7-6(5) 6-3.
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