Big servers Karolina Pliskova, Bianca Andreescu and Reilly Opelka saw their most potent weapon neutralised by strong desert winds as they all crashed out of Indian Wells.
The biggest upset of the day came when tournament lucky loser Beatriz Haddad Maia, ranked 115 in the world, defeated top seed Pliskova 6-3, 7-5 in a match where service holds were rare as wind gusts reached 40 miles per hour.
Meanwhile, Anett Kontaveit beat defending champion Bianca Andreescu 7-6, 6-3 to extend her win streak to eight matches.
Towering American Opelka’s thunderous serve lacked its usual bite as he fell 6-3, 6-4 to Grigor Dimitrov.
The win spelled vengeance for Dimitrov, who lost to Opelka in straight sets at the Canadian Open in August.