World number one Andy Murray was knocked out of the Madrid Open as he lost in straight sets to Croat Borna Coric in the last 16.
Coric, 59th in the world rankings having secured his first ATP Tour title in Morocco last month, won 6-3 6-3.
The 20-year-old broke his British opponent three times in the opening set, and a further break in the second was enough to secure victory.
Coric will face either Grigor Dimitrov or Dominic Thiem in the quarter-finals.
Murray, 29, looked frustrated throughout as his testing clay-court season continued.
This was Coric’s second victory over Murray, having also beaten him at the Dubai Championships in 2015.
In a scrappy opening set, Coric broke to lead 3-2 but a couple of forehand errors allowed Murray to break straight back.
Murray, twice a winner in Madrid, then lost his serve once more, Coric comfortably held and Murray was unable to hold his serve to stay in the set.
His frustration boiled over in the eighth game of the second set as Coric won a long rally to break, before serving out the match.
Murray will next play in Rome, where he is the defending champion.
Djokovic through to quarter-finals
World number two Novak Djokovic reached the quarter-finals with a 6-4 7-5 defeat of Feliciano Lopez.
Defending champion Djokovic, who recently split with his coaching staff, had few problems against the 35-year-old Spaniard.
Belgium’s David Goffin is also through to the quarter-finals after beating Milos Raonic 6-4 6-2, while Kei Nishikori saw off David Ferrer 6-4 6-3.
Rafael Nadal plays Australian Nick Kyrgios later on Thursday.