Rafael Nadal on Monday expressed sympathy for Naomi Osaka following her tearful exit at Indian Wells but believes players should learn to deal with hostile fans.

Four-time Grand Slam champion Osaka was reduced to tears by a heckler on Saturday as she crashed out of the tournament in a straight-sets defeat to Veronika Kudermetova.

It was another uncomfortable moment for Osaka, who put mental health in the spotlight last year after revealing she had suffered from depression.

Speaking after his 7-5, 6-3 third round win over England's Dan Evans on Monday, Nadal said he felt sorry for Osaka, who was subjected to a taunt of "Naomi, you suck" during her loss on Saturday.

However the 21-time Grand Slam king said he believes that players should learn to be ready for hostile atmospheres.

Asked for his opinion about athletes being subjected to negative comments from the crowd, Nadal replied: "These kinds of questions are tough to answer.

"The easy answer for me is 'I feel terrible about what happened, that never should happen.'"

However, Nadal added, "in the real world", abuse from spectators happens.

"Even if is terrible to hear from that, we need to be prepared for that, no?" he said.

"We need to resist these kind of issues that can happen when you are exposed to the people, no?

"I understand that probably Naomi, suffered a lot with these, probably kind of issues that she has, mental (health) issues. The only thing that I wish her is recover well from that and wish her all the very best.

"But the life, nothing is perfect in this life, no? We need to be ready for adversities."

Nadal's comments echoed remarks from Scottish star Andy Murray, who was asked about Osaka following his singles exit on Sunday.

"Obviously I feel for Naomi, that obviously it upset her a lot," said Murray.

"But it's always been something that's been part of sport, I guess, as well. So you have to, I guess, be prepared for that in some ways and be able to tolerate it because it does happen regularly across all sports."