Pablo Carreno Busta has accused Novak Djokovic of feigning injury concerns during their French Open quarter-final on Wednesday.
The Spaniard felt the world No 1 did not have any genuine health issues despite appearing to battle injury problems.
Djokovic, 33, was in trouble against Carreno Busta in Wednesday's quarter-final, struggling with his neck and arm before battling through in four sets. He also called the trainer on court to work on some issue with his upper left arm.
But the Serb recovered well to advance to the semi-finals and later said he had to deal with some physical issues during the early part of his match, without providing much detail.
"Each time he is in trouble he usually does it, that means to say that he was in trouble, that he wasn't comfortable and that I was playing at a high level and was causing him to doubt himself," Carreno Busta told reporters in Spanish.
"Every time a match gets complicated he asks for medical assistance. He has been doing this for a long time. I already knew that. I knew it would happen at the US Open, I knew it would happen here and I know it will keep on happening.
"I don't know if it's something chronic in his shoulder or just mental, but he didn't put me off."
It was against the same player that Djokovic was defaulted a month back in the fourth round of the US Open for inadvertently hitting a line judge with the ball.
"I don't know, maybe it's the pressure or something that he needs to do it. But he continues playing normal, no? I don't know if he's [in] pain really or he has mental [issues]. Ask him," Carreno Busta said in English.
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