Thibaut Courtois says he is focused on representing Belgium at the World Cup amid uncertainty over his Chelsea future.
Chelsea are likely to sell Courtois and are considering entering the race for Roma goalkeeper Alisson, according to Sky in Italy.
He has just a year left on his current contract and the Blues have decided to stop negotiations over a renewal.
But the 25-year-old insists doubts over his club future will not affect his performances in Russia this summer.
"I think I proved at Chelsea the last two months that I don't care about speculation," he said.
"I said what had to be said on that terms. I'm now focused on the World Cup. I think my performances proved that."
Courtois raised doubts over medical reports this week that fellow goalkeeper Loris Karius suffered concussion during Liverpool's Champions League final defeat to Real Madrid.
Karius underwent scans at Massachusetts General Hospital in Boston and medical staff believe the concussion sustained during the final affected his performance in Kiev, in which he made two errors leading to goals.
"It happened to me with Alexis Sanchez - I had a concussion and I couldn't see the ball so after 20 minutes I went out of the game because I couldn't see the ball," said Courtois.
"I feel sorry for what happened with him, but to blame it on concussion that he made those mistakes - he also made two amazing saves. So that was luck then? I don't know because he couldn't see the ball.
It can happen as a goalkeeper but to blame it on a concussion now, I find it strange.
"It's unfortunate for him to have made those mistakes but if you have concussion you will leave the game or the doctors will tell you look you cannot see clearly anymore you must leave the game.
"If they want to say it's because of that, it's OK. He said after the game he made two mistakes, I think everyone will accept that.
"It can happen as a goalkeeper but to blame it on a concussion now, I find it strange. But if medics says that from Boston it's OK."