The 19-year-old Australian conceded that his surprise fourth-round win over Rafael Nadal took a physical toll during his loss to the eighth seed on Court One on Wednesday.
“[The Nadal match] had a pretty big impact,” said Kyrgios. “I was struggling physically about halfway through the second set. I was feeling sore in a couple of places.
“I have nothing left to give. Beating Rafa took a lot out of me but I will work on my fitness and conditioning.
“But I’m not going to take any credit away from him. He served unbelievably. I thought I came out strong on his first return game. I made him earn that.
“All the other service games it looked like he was in such a rhythm that I just couldn’t do anything out there.”
Raonic, meanwhile, expressed his delight at setting up a semi-final showdown with seven-time champion Roger Federer.
“It’s a good feeling,” said Raonic. “It was a very difficult match today. A lot of not knowing what to expect because I knew I played him three weeks ago, but it was very different circumstances this time around.
“I’m happy with the result I was able to get out of it.”
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BIOGRAPHY: Cesc Fabregas