Sunday's penalty shoot-out win over Spurs in the League Cup final means United now have two of the five won, and three are left out there to win.
It's in the next ten days that things could happen to bring the quintuple to within grasping distance.
Next Saturday sees United travel south to Fulham to play in the quarter finals of the FA Cup and a win there will leave them just two games short of claiming that trophy too. Four days after that, Inter Milan come to Old Trafford and the prize for winning this game is a place in the last eight of the Champions League.
If Harry is going to have a bet on this quintuple I'd suggest to him he gets his cash on it now. Mainly because I don't see any mistakes coming from the next three games and by then the odds will have tumbled even lower than the current 10/1 on offer.
"Only you guys, the media, will get carried away with it," he said. "We'll keep our feet on the ground. My experience is we could go to Fulham this weekend in the FA Cup and the ball comes off somebody's backside and we are out of the cup. That is what cups can do to you. The best thing we can do is gather ourselves, energise ourselves for Newcastle on Wednesday, which will be a very difficult game for us, and go from there, taking it one step at a time."
Redknapp believes United's squad has sufficient depth of quality to make their own luck.
"They have got a big chance—they are the team to beat for sure, they have a fantastic squad. They have one cup already, it looks as if the league is going their way for sure and you wouldn't bet against them in the Champions League and the FA Cup."
They said the Treble was impossible and Fergie won it. They said a quadruple is beyond any team, and yet here is Fergie again going for the impossible. A quintuple? Maybe, just maybe...