The Reds have already added one more match to the busy schedule - this Wednesday's third-round replay against West Ham - but Crerand insists this was preferable to the fate that James Collins' two goals seemed to have inflicted in the first meeting.
"I travelled back on the train with a lot of United fans after the game at Upton Park and there was a sense of relief that we’re still in the competition," wrote Crerand, in his column for Sunday's United Review.
"There’s a real enthusiasm from everyone to see us win it again. You only needed to see the manager’s reaction to Robin van Persie’s fantastic late equaliser – he was over the moon.
"Make no mistake United are in it to win it. Okay, so the replay is a game we could have done without, but we have a lot of players back from injury now and a big squad, and in the long term I don’t think a few extra cup games will damage our league and Champions League aspirations too much."
Writing to fans in the same edition of United Review (Liverpool), Sir Alex said: "I rested a few players at West Ham – van Persie, Ferdinand, Carrick, Evra and Young all enjoyed some measure of a break - and I shall continue to juggle my squad because while December was a busy month there is still no let-up.
"The replay with West Ham is quickly followed by a trip to Spurs and then hopefully we’ll have a fourth round tie against either Fulham or Blackpool to give us another two-game week before another busy week with fixtures against Southampton and