West Ham manager David Moyes has confirmed Lucas Paqueta has undergone a medical at the club.
The Brazilian midfielder will join the Hammers from Lyon in a deal that could eventually rise to €60million including add-ons.
"I understand he's had a medical today, I've not ben able to confirm yet if it's all good or all bad," Moyes said, following Sunday's 1-0 victory over Aston Villa.
"I'm obviously really hoping it comes off because I think he's an excellent player, he can add something for us.
"He's another exciting player for us. We've brought in several players and a lot of them are full internationals.
"It's been a difficult window but trying to add something at a level to keep us up there is what we've tried to do. I'm grateful to the board and the club for trying to get the best we can."