It is being reported that Hull City, who paid £3 million for Andy Robertson two years ago, are ready to offer £1m for Spittal during this transfer window.
Rankin feels the 20-year-old has the star quality to follow in the footsteps of Robertson, Ryan Gauld, Stuart Armstrong, Gary Mackay-Stevens and Nadir Ciftci onwards and upwards from Tannadice.
However, with United 11 points adrift at the foot of the table and facing the arduous task of Celtic tomorrow night, Rankin is desperate for Spittal to stay and help in their bid to avoid relegation, having scored spectacular free- kicks in the last two matches against Dundee and Airdrie.
Rankin said: “There is nothing to stop Blair going onto the next level like Andy, Ryan, Nadir, Stuart and Gary. He’s got the speed, the strength, the ability and the delivery.
“Somebody said after the Dundee game he couldn’t have put the free-kick into a better position. But, then at Airdrie, he really has because it was right in the top corner. It was fantastic.
“We see him do it every day in training. He stays behind and spends a lot of time on it. It’s come off for him two games in a row – so there’s no pressure on him for Friday night’s game against Celtic.
“At this moment we’ll use any little thing as motivation, although looking at the league table we shouldn’t need anything extra. Being bottom should spur us on anyway. I certainly don’t want a relegation against my name. It doesn’t look good, but that’s the position we’re in and we have to respond, starting on Friday.
“If Blair continues to perform the way he has, then there’s no reason why we won’t rise up the league. He was magnificent last week against Dundee and then once more at Airdrie he produced another moment of brilliance with the free-kick.”
Rankin feels it is A credit to Spittal that he is attracting interest from Steve Bruce when United are in such a perilous position in contrast to the top-three finishes enjoyed in recent seasons.
He added: “I think it has been harder for Blair. You look at our league position over the last couple of years and it will have been easier for boys to shine. They’ll have had more freedom to do things. But Blair finds himself in an unfortunate position because we’re bottom of the league right now.
“It’s been good, though, to see someone else on the scoresheet. The goals are starting to be spread out amongst the team after a long spell relying on Billy McKay. Winning at Airdrie last Saturday has given everyone a lift. It was massive and you can see the difference in everyone.
“We need to go on a run by putting six or seven results together to gain momentum and put a bit of pressure on the teams above us. I don’t see any reason why we can’t.”