Lascelles admits there's been no discussion amongst the players about swapping shirts with Kylian Mbappe.
He told Chronicle Live: "It's crazy. I know I have been here a long time but I never thought I'd be standing here in the position I am in now and I am so grateful that I am. I am just so thankful.
"It is something that you really have to relish as an experience. Not many footballers can be in this position, being involved in the Champions League. I am grateful that the manager has got us in this position and that the boys have got us in this position."
Asked about Mbappe's shirt, Lascelles said: "It's not something we have really spoken about. We are just focusing on how the manager sets us up as players.
"We are looking to stick to the game plan and win the game. That's all we care about. We don't care about names and stuff like that.
If he (Mbappe) asks me? "Yeah, when we get to the tunnel but on the pitch it's just business.
"Kylian Mbappe is probably the best player in the world. We just need to be professional and that's what we are. It's just about getting the job done."