Mats Wilander believes Nick Kyrgios may prove to be the 'nightmare' opponent for Rafael Nadal when they meet in the Wimbledon semi-finals.
Nadal came through a very tough quarterfinal against Taylor Fritz on Wednesday, but he aggravated his abdominal injury in the process.
It visibly affected his game, with his serve and backhand slice noticeably reduced for much of the match.
It remains to be seen what kind of physical condition Nadal will be in for the semi-final clash with Kyrgios, but Wilander is concerned for the Spaniard.
"It’s impossible to say [if he will recover in time to play Nick Kyrgios]," he told Eurosport.
"I remember we did a famous interview on Phillippe-Chatrier after the [Roland Garros] final a few weeks ago and he said he had a couple of injections in his foot and his foot was put to sleep.
"Can you do that with your abdominal muscles? Maybe he can still figure out a way to serve at a decent speed?
"I am assuming he is not going to hit any tennis balls tomorrow and he’s going to take it very easy and recover.
"Who is the nightmare opponent when you are feeling like this? Novak Djokovic, yes. But also Nick Kyrgios. It’s the worst news ever [for Nadal]."
After the defeat to Rafael Nadal, Taylor Fritz admitted it was his toughest defeat in tennis and it left him 'wanting to cry.'
Wilander, though, does not believe the American should be too hard on himself, simply because of Nadal's supreme ability to problem solve.
"Does the crowd lift [Nadal] through today's match? Most probably," Wilander said.
"But I think Rafa turns into a tactician and a competitor who sees a guy who is more wounded on the other side in Taylor Fritz.
"We can’t call this a choke, but this is going to hurt Taylor Fritz big time to have not beaten Nadal today. It doesn’t look like the injury affected him running, he was running well, he was hitting forehands and backhands well.
"The mind of Rafa Nadal tactically is just so knowledgeable, it’s incredible that he could win this tennis match, on grass, without a serve."
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