With no European commitments, United now face a break before facing Aston Villa on March 15. Carrick's side, who still sit third in the Premier League table, will travel to Bournemouth five days later.
"Today is a real disappointment and the feeling is really bad, but we have a couple of days and I think weeks where we need to get together and we need to think about how to react," Lammens concluded. "Starting from tomorrow, it's going to be like this and in training keep the intensity going that we can deliver in the games and then react in the next game."