Gary Neville thinks Manchester United need to follow Manchester City by spending big on full-backs.
Pep Guardiola has spent over £130million on full-backs, bringing in Kyle Walker, Benjamin Mendy and Danilo and Neville thinks United need to do the same.
Ole Gunnar Solskjaer is believed to be in the market for a right-back with Antonio Valencia leaving the club in the summer and United's former right-back thinks big money needs to be spent.
"I don't know why United have had such problems at right-back. You can't keep signing full-backs for £15m. Over the past few years they've spent nearly £100m on five full-backs," Neville told Sky Sports.
"City spent big on Kyle Walker, Danilo and Benjamin Mendy. Maybe United would be better buying the correct full-back first time up for £40m or £50m and have them for seven years, because it's cost them that much in the end trying different full-backs."
Ashley Young has been criticised in recent months for his performances but Neville has defended the England international who is a converted winger.
"Ashley Young is not the person to start criticising at Manchester United; he's been asked to play right back, left back, left wing back, right wing back," Neville added. "He's doing it brilliantly well, but he's not a right back! I think Antonio Valencia did well for two seasons but I think he was more of a right winger."
