After apparently being out of the Premier League title race, Manchester United are suddenly right back in the thick of things.
In following up their north London derby triumph over Arsenal by beating Chelsea at White Hart Lane on Saturday, Spurs had inadvertently thrown United a lifeline at the same time as giving their own top four hopes a massive lift.
But for the Red Devils to capitalise on their good fortune, and pile the pressure on Carlo Ancelotti, whose side do not meet Stoke until Sunday, they must beat Spurs 24 hours earlier, a result that will see them go top, however briefly.
"Your emotions change from week-to-week depending on who is playing," said the midfielder.
"It is funny how the fixtures have come together. At the start of the season you could never have predicted the scenario that has unfolded.
"You are supporting one team one week and playing against them the next. That is the nature of the game."
Although he has won three championship medals and a Champions League since he quit Spurs in an £18.6million deal, Carrick has kept a close eye on the fortunes of his old club and says United will take nothing for granted at the weekend, despite the stakes being so high.
"Tottenham have been around that fourth spot all season," said Carrick.
"The squad they have assembled over a number of years is really top class.
"We are at the business end of the season now and you have to give them credit.
"They have put in some excellent performances after the disappointment of that FA semi-final defeat by Portsmouth."
Should United get the result they want, Carrick would then have a tricky decision to make about whether to watch Chelsea's Stamford Bridge encounter with Stoke.
The temptation is to plonk himself in front of the TV, but knowing the agonies he could be put through, a day away from the box might be a better idea.
"I can't watch games," he said.
"You can't control the match, which makes it really hard.
"Sometimes it is better to take your mind off it and just get the result after it is all over."