Manchester United fans are furious at the prospect of the club missing out on Sergio Reguilon to Tottenham Hotspur.
M.E.N. Sport understands that United are working on up to three more signings before the October 5 transfer deadline, having already signed Ajax playmaker Donny van de Beek.
While attacking signings remain the priority and Borussia Dortmund star Jadon Sancho is still the club's top target, the club are also considering a move for a new left-back due to uncertainty in the position.
Luke Shaw's absence was keenly felt at the tail end of last season, with United losing two semi-finals, after he was ruled out with an ankle injury. His replacement, teenager Brandon Williams, struggled for form on his weaker side, with Marcos Rojo, Diogo Dalot and Timothy Fosu-Mensah the only other options at left-back.