Jose Mourinho is keen on strengthening his defence during the January transfer window, especially the full back areas, but the Manchester United hierarchy are said to be reluctant to spend on a marquee signing and are rather looking for economical alternatives.
Danny Rose has been high on the priority list for the Portuguese coach, but the Tottenham Hotspur left-back is valued at £50m ($67.7m) and is unlikely to be allowed to leave the club midway through the campaign.
According to the Daily Record, Mourinho's other priority signing Alex Sandro is also out of the budget at the moment with Juventus demanding close to €70m (£62.2m) for the left-back, who is also wanted by Antonio Conte at Chelsea.
The report claims that the 20-time English champions' scouting network have identified Celtic's Kieran Tierney and Fulham's Ryan Sessegnon as cheaper alternatives to the aforementioned duo. They are said to believe that the duo can help in strengthening Mourinho's defence while also not hurting the club coffers as much.
Tierney has been a long-term target for Premier League clubs, but the Scotland international has chosen to stay with the Scottish Premier League champions and is unlikely to push for a move even if the interest is made.
Sessegnon, on the other hand, could be tempted to leave and has been linked with a move to Tottenham in recent weeks. Mauricio Pochettino is said to be a big admirer of the left-back, and has been eyeing him as a potential replacement for Rose, who has been linked with a move to United since last summer.
United's stance to target a young left-back with future potential rather than an experienced player like the manager wants is said to be due to Luke Shaw's return to form. The former Southampton defender has struggled to recapture the form that earned him a £27m move from St Mary's to Old Trafford in 2014.
The England international had fallen out of favour under Mourinho after the Portuguese coach questioned his understanding of the game last season, and until mid-December this campaign he had not featured in the Premier League. The Red Devils boss preferred to use Matteo Darmian, Ashley Young or Daley Blind in the left full back position.
However, owing to injuries and suspensions in recent weeks, Shaw has found himself starting games. He has played the full 90 minutes in the last three Premier League games and his performances and desire to return to the starting XI is said to have impressed Mourinho. This is said to have prompted the club to look at younger players rather than more experienced stars to provide competition at left-back.