Australian Open champion Jannik Sinner extended his winning run to 19 matches with a comfortable win over Jiri Lehecka to reach the semi-finals at Indian Wells.
The Italian beat the Czech player, ranked 32 in the world, 6-3 6-3.
"He [Lehecka] has huge potential so I was really aware of every point that I made," said third seed Sinner, 22.
Sinner will face defending champion Carlos Alcaraz or German Alexander Zverev in the last four.
World number two Alcaraz, who beat Sinner at the same stage of the tournament last year on his way to lifting the trophy, faces sixth seed Zverev later on Thursday.