Tennis players lashing out at umpires is hurting the sport and tougher punishments need to be imposed to discourage it from happening, Rafael Nadal told reporters on Thursday.

Nadal’s comments came after Alexander Zverev received a one-year probation — but no immediate suspension — following an outburst in Acapulco last month where he smashed his racket against the umpire’s chair and verbally abused him.

Given the intensity of Zverev’s tantrum and the proximity to the chair umpire’s ankles, many were surprised the 24-year-old German was allowed to compete at the Indian Wells tournament.

“I have a good relationship with Sascha, I like him, I practise with him very often, so I wish him all the very best. And he knows that he was wrong and he recognised that very early and that’s a positive thing,” Nadal said.

“On the other hand, if we are not able to control this type of attitude on court, not just this one instance in particular, there has been other stuff going on in the last couple months.

“If we are not able to penalise these types of attitudes in a little stronger way, then we as players will feel stronger and stronger all the time.

“In this sport, we have to be a positive example, especially for the kids.”