Giant Croatian Ivo Karlovic won the battle of the big servers on Tuesday when he came from a set down to edge Greg Rusedski 6-7, 7-6, 7-6 in their first round clash at the Madrid Masters.
Karlovic, who also beat the British number two when they met at Washington earlier this season, reeled off 28 aces on his way to a victory that took two hours and 17 minutes.
The 26-year-old, who at 2.08 metres is the tallest man on the ATP circuit, will now face another big hitter in second-seeded Andy Roddick of the United States.
"If you could have written the worst draw for me then this was it," said Rusedski. "With the altitude here and the hard courts his serve was even faster than usual and it's not fun for anyone to play him.
"I didn't do much wrong and didn't lose my serve but he played some really good tennis."
The two men rattled through a succession of booming service games in the opening set although it was Rusedski who tried to mix up the game a little more and move his bigger opponent around the court.
Unsurprisingly the set went to a tie-break, with Rusedski finally getting the better of his opponent after a mini-break and finishing off with an ace to win through 7-5.
It was more of the same in the second set, the two players firing off a battery of 200 kph serves as they matched each other game for game through to the tie-break.
This time, though, it was Karlovic who won through, taking advantage of a Rusedski volley error at the net to win the tie-break.
There was nothing to separate the two players in the third set either but Rusedski lost his concentration after being foot-faulted several times.
He misjudged a Karlovic passing shot that clipped the line in the tie-break and was then caught out by a whipped forehand cross court from the Croatian before losing 7-3 in the decider.
Christophe Rochus defeated French youngster Gael Monfils 6-4, 6-4 victory in a first-round match on one of the outside courts.
The Belgian qualifier will face fourth-seeded Argentine Guillermo Coria in the second round.
Fifth seed David Nalbandian, who lost to Marat Safin in last year's final, plays Juergen Melzer in a second round match later on Tuesday, while local favourites David Ferrer, Carlos Moya and Juan Carlos Ferrero are also in action
Top seed and world number two Rafael Nadal is set to make his debut in a second round match against Victor Hanescu of Romania on Wednesday but there is still a question mark over the 19-year-old's participation because of tendinitis in his knees.