Rafael Nadal edged arch-rival Roger Federer in a thrilling decider in the "battle of the surfaces" in Mallorca.
The world's top two players slugged it out in an exhibition match on a half-clay, half-grass court before the Spaniard prevailed 7-5 4-6 7-6 (12-10).
Nadal broke Federer on both grass and clay to take the opening set before the Swiss broke on clay to level the match.
The players traded breaks in the third set before clay king Nadal edged out the grass master in a tie-break.
Federer, Wimbledon champion for the last four years, has won 48 consecutive matches on grass, while double French Open champion Nadal has won 72 straight matches on clay.
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The organisers of the event had to lay a brand new surface on the grass side of the court on Tuesday night after the original turf had failed to cope with the indoor location and then fell victim to a plague of worms.
Changeovers were extended to two minutes instead of the usual 90 seconds to give players a chance to change their footwear for each surface.
"It allowed us to play for points without much tension and to play more relaxed "
"It has been a nice experience, although before the match I thought it would be a disaster because I felt it would be very difficult for me to adapt to the court," said Nadal.
"I have had a good time and that is important.
"Both of us would like to repeat this experience because, although the match was not a real one, it allowed us to play for points without much tension and to play more relaxed."
Federer said: "I found the court to be excellent, especially the clay part. The challenge was difficult, because you have many things in your head.
"You have problems to work out about how you are going to play on either side of the court.
"On the grass, I felt at the start that I was moving very well, although it took me a while longer to adapt to the clay."