Spaniard Albert Ramos dumped world number one Andy Murray out of the Monte Carlo Masters 2-6 6-2 7-5 on Thursday after firing back from 4-0 down in the final set to take his place in the quarter-finals.
Murray, who suffered an elbow injury in March and made his return from a five-week layoff on Wednesday after a first-round bye, won the opening set in 48 minutes before losing concentration.
Left-hander Ramos, ranked 24th in the world and the 15th seed, ripped through the second set in 36 minutes and refused to give up after the Scot had romped to a 4-0 advantage in the third with victory beckoning.
The Spaniard won four games in a row before Murray, his serve misfiring, applied some late pressure. But Ramos was implacable as he won the next two with back-to-back breaks and served for the match.
Murray saved one match point before hitting a return into the net to hand Ramos an impressive victory over his top-ranked opponent in the first European claycourt tournament of the season.