Mjallby midfielder Otto Rosengren admits Manchester United's interest has come as a shock.
Mjallby sporting director Hasse Larsson has confirmed United have requested tickets for games to check on the youngster.
United scouts watched him again last week at IF Brommapojkarna, reports Fotbollskanalen.
Rosengren said, "It is quite powerful. But then, of course, you can't think about that when you're playing. But when you think about it, it's quite big.
"I didn't know that club was here, I didn't even know they had been to Strandvallen. I was shocked when I read about it. I sat at home and saw when it came out, it said that United are scouting me, I was a little shocked.
"There is interest, but it is nothing concrete as far as I know. You have to take a stand if there is something concrete, an offer or something like that. I have a contract to 2025."