United are desperate for fresh faces this summer and have so far brought in Daniel James and Aaron Wan-Bissaka.
And the Telegraph say there are fears among the United hierarchy that there seems to be a specific tax just for themselves.
The Old Trafford club look set to return for the defender in the coming weeks, with the Serie A side likely to demand a fee of around €50m.More news: Diaz shoots 62 to lead John Deere Classic
And Leicester are eager to secure a world-record fee for Maguire, having snubbed United's opening offer of £75m.
Solskjaer, meanwhile, recently got tough and said United would not overpay for any player.
With Pogba being heavily linked with moves to Juve and Los Blancos, Solskjaer will reportedly only allow him to leave at the end of the 2019/20 campaign.
The player who has scored 31 times and assisted 18 in 162 appearances for Lazio has been valued at a mammoth price of £90 million by the clubs president who wouldn't be willing to lower that price.More news: OPEC forecasts oil demand to grow in 2020
Lukaku has an ongoing problem, says the report, and hence the idea was not to aggravate the same by doing regular exercises with the rest of the United players.
The Frenchman was also pictured when Manchester United unveiled their home strip for the upcoming season, which was inspired by the club's 1999 Treble-winning heroics. United are also on the lookout for a center back and this has led them to renew their interest in Fioretina's Nikola Milenkovic.
Real Madrid are taking a patient stance when it comes to "Operation Pogba".More news: Maduro hopeful about Barbados talks with Venezuelan opposition