Gary Neville says Luke Shaw's biggest challenge at Manchester United is to stay fit.
The left-back has enjoyed a renaissance at United this season, becoming the best performing full-back in the Premier League thanks to his attacking intent.
It is a far cry from when he was struggling for fitness under Jose Mourinho and criticised repeatedly.
Speaking on Sky Sports, Neville said that Shaw can become a driving force for United in big games where they have struggled to break teams down this season.
Yet he says that will be dependent on the 25-year-old being able to avoid injuries and stay match fit.
He said: "When the lads mentioned his lack of fitness, it’s a bit of a cycle for Luke in the sense that the type of body he has.
"His body isn’t conducive, I’ve got one of those bodies as well that when you’re not active, it doesn’t quite do as what you think it should do and then it becomes a bit of a cycle when you lose a bit of confidence and your fitness isn’t right.
"I’ve been there, at the end of my United career where I was picking up injuries, if he stays fit then I have complete belief in him.
"Roy Keane mentioned before about United struggling in big games or some games where they can’t break teams down.
"But I actually think he’s the driving force when Manchester United are drawing in a game and look like they need a goal.
"He’s a really good defender as well, he doesn’t make many mistakes. He’s good at the back post, good in the air, better in the air than we give him credit for.
"If he can stay fit, he’s England’s best left-back this season, he’ll play at the Euros if he stays fit, it’s all about Luke Shaw staying fit."
