The gloveman managed to nab the Barcelona playing shirt of the Argentine maestro following the Hoops' 2-1 Champions League on Wednesday night and he admits it is a piece of memorabilia he will treasure.
"It was a fantastic night to beat Barcelona," Forster told SunSport.
"The atmosphere was even better than an Old Firm game. And to get the win as well made it incredible, especially as it was Celtic's 125th anniversary.
"I've got Messi's shirt which is a nice souvenir of the occasion.
"I went after him to ask if I could have it and he was happy to give it to me. He just said 'No problem'.
"It's not going to fit me seeing as he's only 5ft 7ins and I'm 6ft 7ins - but I'm going to get it framed to put on the wall.
"I've no idea what he'll do with mine. I think it might be a bit too big for him!"