United have utilised both players in a 3-5-2 formation in recent matches, including the 1-1 draw with Brugge on Thursday.
Neville feels Shaw's switch from left-back into one of the back three has paid dividends.
"I think Luke Shaw is approaching something like his best in that left centre back position," Neville said on Twitter.
"He looks strong and has his running back to where it was. I hope he stays clear of injury now."