Peterborough boss Darren Ferguson has admitted his side are "shattered" ahead of the trip to Oldham this weekend.
Posh drew with Colchester on Saturday in what was their sixth game in 21 days and Ferguson may have to make changes at Boundary Park.
He said: "League One is tough on you physically and mentally. We looked very leggy, shattered even, at the end of the Colchester match, but that's what happens when you play Saturday, Tuesday, Saturday.
"That sort of schedule will affect every team, but I am lucky enough to have a committed set of lads who will keep going no matter what. They showed that again on Tuesday.
"I will try and freshen the lads up before the weekend. We will do some physical tests on the players to see how they are coping and we may even let some miss training.
"I'm hoping to train at Manchester United on Friday which will give the lads a boost ahead of our match at Oldham."