World number two Novak Djokovic was knocked out of the Mexico Open quarter-finals in straight sets by Australian Nick Kyrgios.
The Serbian top seed lost 7-6 (11-9) 7-5 in one hour, 47 minutes in what was the first-ever meeting between the two.
Djokovic, 29, was back in action in Acapulco this week for the first time since his second-round exit at the Australian Open in January.
Kyrgios, 21, faces American Sam Querrey in Friday’s semi-finals.
Spain’s Rafael Nadal and Croatia’s Marin Cilic meet in the other semi-final.
In the women’s event, there were wins on Thursday for Ukraine’s Lesia Tsurenko and Croatia’s Mirjana Lucic-Baroni.
