ALEX Ferguson admitted he left Ruud van Nistelrooy and Roy Keane out of Sunday's FA Cup victory to save them for Wanderers.
Ferguson is taking nothing for granted against Sam Allardyce's men on Wednesday night and wants his best side available and as fit as possible.
Ferguson defended his decision to leave van Nistelrooy and Keane out of the starting line-up after two goals from Paul Scholes gave United a 2-1 victory at Aston Villa to put them into the fourth round.
He said: "Wednesday's match is massive.
"Bolton left a lot of players out of their team on Saturday, so it was never my intention to start with Roy or Ruud against Villa.
"Roy is never going to play all the games and we have to be careful with Ruud and make sure he is available for the major ones."
Comments: Our rules
We want our comments to be a lively and valuable part of our community - a place where readers can debate and engage with the most important local issues. The ability to comment on our stories is a privilege, not a right, however, and that privilege may be withdrawn if it is abused or misused.
Please report any comments that break our rules.
Read the rules hereComments are closed on this article