Britain’s David Haye hopes Saturday’s fight with Arnold Gjergjaj will raise more than £50,000 for Nick Blackwell.
The 25-year-old Blackwell will not fight again after sustaining serious head injuries in his middleweight fight against Chris Eubank Jr in March.
Haye, 35, has pledged to donate 10% of the money from ticket sales for the bout at London’s O2 Arena to Blackwell.
“I had a good chat with him. He is in good spirits and sounds as sharp as a tack,” said heavyweight Haye.
The Londoner, who is fighting for the second time since a comeback from retirement, added: “I was worried about how Nick was going to be but he sounds better than ever.
“It’s really good knowing he’s coming to the fight to do a bit of commentary.
“I am not sure how much it will be but I’ve been aiming to get at least £50,000, that would be a nice lump to help him move on.”
Meanwhile, Haye has dismissed concerns from former undisputed world heavyweight champion Lennox Lewis, who says his bigger physique hinders his speed.
Haye said: “My speed feels as quick as ever, if not faster. If I was fighting Anthony Joshua, I would do the same training.
“I’m stronger now than ever. I’ve done a nice solid strength programme in camp to maintain my weight. I am about 103kgs now. I was about 108kgs a month ago, and as I have sped up, my weight has just come down.”
In January, Haye fought for the first time in more than three years and knocked out Australian Mark de Mori in the first round.
Gjergjaj, who was born in Kosovo but lives in Switzerland, has won all 29 of his professional contests, while Haye, a former cruiserweight and heavyweight world title holder, has lost two of his 29 fights.