Rafael Nadal suffered a chastening defeat in the Monte Carlo Masters semi-final on Saturday, losing to Italy's Fabio Fognini 6-4, 6-2.
It was a strangely wayward display from Nadal, who led 3-1 in the first set before eventually holding off three match points when Fognini served to win the second set 6-0.
In the end, the Italian world No 18 still closed out an emphatic victory, leading Nadal to describe his performance as "one of my worst matches on clay in 14 years." Given the Spaniard's unprecedented success on clay, it's hard to argue with that statement.
But it did get us thinking: what other Nadal performances could rival the Monte Carlo defeat? Here are five more:
Hamburg Masters 2007: v Roger Federer (6-2, 2-6, 0-6)
In the 11th meeting of what would become one of tennis' great rivalries, Federer stood little chance against a 20-year-old Nadal already laying claims of being the greatest claycourt player of all time.
The Spaniard was on an 81-match winning streak on clay, claiming 13 consecutive titles including two French Opens, in a run going back more than two years.
After taking the first set 6-2, it appeared to be business as usual. But Federer produced a rousing comeback to limit Nadal to just another two games for the rest of the match and earn the first of just two claycourt wins over his rival.
Nadal would earn his revenge weeks later by beating Federer in the French Open final for his third successive Roland Garros title. He would also avenge this defeat 12 months later by winning the Hamburg title in three sets against Federer.
French Open 2009: v Robin Soderling (2-6, 7-6, 4-6, 6-7)
Nadal entered this fourth round match as the four-time and defending champion who remarkably had never lost a match at Roland Garros. His opponent had never been to this stage of a grand slam before and had won just one game when the pair met a month prior at the Italian Open.
So even after the Swedish 23rd seed stormed through the opening set, he was still given little chance of beating the 22-year-old Spaniard, particularly when Nadal levelled after taking the second set in a tie-break.
However, Soderling reclaimed the advantage in the third set before closing out the most unlikely of victories in a tie-break. He would go on to reach the final, losing to Roger Federer. Soderling eventually retired at the age of 26 after contracting a career-ending bout of glandular fever.
Nadal, meanwhile, bounced back to win another seven French Open titles.
Madrid Masters 2012: v Fernando Verdasco (3-6, 6-3, 5-7)
The 2012 European claycourt swing was going much the same we have come to expect from Nadal: he arrived in Madrid having won the Monte Carlo and Barcelona titles and was overwhelming favourite to claim his third crown in the Spanish capital.
He was an even bigger favourite against Verdasco having beaten his fellow Spaniard in all of their previous 13 meetings. It looked set to be win No 14 when Nadal led 5-2 in the final set, only for big-hitting Verdasco to come roaring back and claim victory after three hours and 11 minutes.
Nadal was critical of his performance, insisting he was "never in control of the match, I didn't know how to win a point", but the Spaniard was equally scathing of Madrid's controversial blue clay courts.
Madrid would revert back to red clay and Nadal would go on to win this tournament a further three times.
Wimbledon 2013: v Steve Darcis (6-7, 6-7, 4-6)
With shock results on clay scarce, it has been on the grass where Nadal has found the going a bit tougher, despite twice winning Wimbledon.
Second round defeats to unheralded Lukas Rosol and Dustin Brown, in 2012 and 2015 respectively, were disappointing results, but none were more surprising than this first round defeat to Belgium's Darcis - a player ranked 130 places below him.
Nadal had two weeks earlier won his eighth French Open title after recovering from a knee injury but he struggled to adapt to the grass in a straight sets defeat. It was the first of just two first round grand slam defeats in Nadal's career.
Australian Open 2019: v Novak Djokovic (3-6, 2-6, 3-6)
Losing to top seed Djokovic wasn't necessarily a shock but the manner of defeat certainly was. Nadal had been in ruthless form to reach the final in Melbourne, but was completely out of sorts against his great rival.
A single break in the first set flattered Nadal who was constantly under pressure on serve while failing to make any inroads on Djokovic's service games. The second and third sets were more emphatic, with Djokovic claiming two breaks in both sets to seal an easy win in just over two hours.
What was expected to be a fierce contest between the two best players in the world turned out to be a walk in the park for the Serbian.
