West Ham boss David Moyes admits facing Manchester United tomorrow is a mental challenge for his players.
West Ham go into Saturday's early kickoff on the back of their Carabao Cup quarterfinal thrashing by Liverpool.
Moyes said: "Mentally it's a big ask again for the players, but we'll be up for the game and ready to play. Hopefully we'll put in a good performance.
"It's a completely different competition. We're just off the back of a really good league win against Wolves when we won 3-0 at home.
"Our form has been pretty good so we want to keep that up and we'll try to do that against Manchester United.
"There's no time to dwell on Wednesday, not at all, and we won't.
"We're in a good position in the league. We're in Europe, we've qualified top of the group again this year, so we'll move onto the next game and put the other one away now."