No doubt they have watched him, several times, goodness knows they have enough scouts out there to watch every twitch of every player.
But why the story linking United with Collins right now?
Could it possibly have anything to do with events over the past five days?
First Collins is recalled to the Stoke line up for his first league start since Michael O’Neill took charge and does pretty well in the 0-0 draw at Blackburn last Wednesday.
Then three days later, not completely out of the blue, he is left out again to accommodate the return of the more experienced James Chester at Luton.
Sounds ripe for a story that one!
Time will tell just how serious United’s interest is, but most took it with a pinch of salt when they were first linked to Collins last summer.
Not least the 18 year-old defender himself.
Such a story could turn the head of most teenagers, but he has his screwed on firmer than most and appears to be surrounded by equally level-headed people.
Like Tyrese Campbell, his development is surely best served at Stoke, certainly for now, and hopefully he and those closest to him appreciate as much.