Andy Murray is out of the Monte-Carlo Masters after suffering a shock defeat to Albert Ramos-Vinolas. But sitting here, being 4-Love up in the third, I haven't lost many matches like that in my career.
"I'm disappointed to lose from the position that I was in", said Murray, last year's French Open runner-up. The Croatian reached the last eight after beating No 9 Tomas Berdych 6-2 7-6 (0).
Later, nine-time champion Rafa Nadal of Spain survived a second-set blip against Briton Kyle Edmund to go through 6-0, 5-7, 6-3.
Murray's serve, in particular, was the source of many problems and he was broken by the 15th seed on seven occasions - the first time that's happened in a best of three sets match since he lost to Rafael Nadal at the same venue in 2011.
Murray, who was making just his second appearance since a second-round loss to Vasek Pospisil at Indian Wells in early March, was not too concerned with his serve.
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.
Third seed and former champion Stan Wawrinka dropped a set to Jiri Vesely, who defeated Novak Djokovic here last season, but recovered to win 6-2 4-6 6-2.
"Maybe the technique changed a little bit".
Fifth seed Marin Cilic of Croatia destroyed France's Jeremy Chardy 6-3 6-0.
Ramos-Vinolas, of Spain, celebrated his first win over a world No. 1 in four chances.
That seemed to be a positive thing for Murray, who had won all five of their previous meetings, but the 29-year-old made a decidedly ropey start. I served much better today than I did yesterday.
Novak Djokovic will want to keep his preparations for the French Open to stay on course when the world number two faces off against the risky David Goffin in the quarterfinals of the Monte Carlo Masters on Friday.
On the other hand, Goffin stunned sixth seed Dominic Thiem in a three-setter (7-6, 4-6, 6-3) to move a step closer to his maiden ATP Masters 1000 semi-final.
He sent a backhand wide on his first match point and then clinched victory when Murray's backhand hit the net.
Nadal will now face the victor of another pre-quarterfinal clash between Buenos Aires' Diego Schwartzman and Germany's Jan-Lennard Struff.