Andy Murray and Stan Wawrinka were bundled out of the Monte-Carlo Masters on Thursday, but Novak Djokovic and Rafael Nadal reached the quarter-finals in contrasting fashion.
Albert Ramos-Vinolas fought back from 4-0 down in the final set to claim the scalp of top seed Murray, who went down 2-6 6-2 7-5 on the clay in the principality.
The world number one was not the only big name to bow out, as US Open champion Wawrinka was beaten 6-4 6-4 by Pablo Cuevas.
Twelve-time grand slam champion Djokovic showed he still has work to do in order to return to the peak of his powers, but saw off Pablo Carreno Busta 6-2 4-6 6-4.
Fourth seed and defending champion Nadal only needed 68 minutes to beat birthday boy Alexander Zverev 6-1 6-1.
MURRAY RUES 'BAD DECISIONS'
Murray looked bound for the last eight when he won the first four games of the deciding set, but the three-time grand slam champion was left stunned by a defiant Ramos-Vinolas.
The top seed grew increasingly disgruntled in the final set as Spaniard Ramos-Vinolas turned the tide to seal the biggest victory of his career and book a last-eight meeting with Marin Cilic.
Wimbledon champion Murray said: "A few times, I made some bad decisions. That's something that, with my team, I'll look at, watch some parts of the match over, see the shots that I chose and what I would do differently."
WOE FOR WAWRINKA
Cuevas had never beaten a top-four player before stepping out on court against Wawrinka, but needed just the two sets to put that record right.
The 16th seed from Uruguay did not face a solitary break point against the three-time grand slam champion in the first meeting between the two.
DJOKOVIC PASSES CARRENO BUSTA TEST
Djokovic was in danger of following Murray and Wawrinka out of the tournament, but hung in there to get past a defiant Carreno Busta and seal a clash with David Goffin.
It looked set to be plain sailing for the world number two when he won six games in a row to lead 2-0 in the second set, but the Spaniard was not finished yet.
Djokovic lost the next five games before Carreno Busta took it into a decider and the underdog had the Serb in trouble at 15-40 and 4-4 in the final set, but was unable to pull off a shock.
NADAL SPOILS THE PARTY
Nine-time Monte Carlo champion Nadal did not come bearing gifts on Zverev's 20th birthday, racing to victory in a one-sided contest.
The Spanish great broke five times as he won at a canter and will now face Diego Schwartzman, who reaches his first Masters quarter-final with a 6-3 6-0 demolition of Jan-Lennard Struff.
Lucas Pouille will take on Cuevas after the Frenchman was given an easy passage into the last eight, with compatriot Adrian Mannarino retiring due to a hip injury early in the first set.
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