At 3-0, N'Golo Kante went forward having not been tracked by Herrera, weaved between Pogba and Chris Smalling to finish past David De Gea and Neville believes that the midfield pair could have done a lot more to concede the goal.
"For the fourth goal... Herrera and Paul Pogba there, I think it's absolutely scandalous," the former United man said on 'BBC' programme 'Match of the Day'.
"The way Kante runs in behind Pogba - Herrera can see the run as well but doesn't track him - then he's one-on-one with (Chris) Smalling and it's just too easy.
"He shouldn't be allowed to run in behind Herrera".
Neville believes that United made some unforgivable mistakes, but concedes Chelsea were "fantastic".
"The mistakes they [United] made in the game, you can't legislate for that as a coach. United had opportunities to get back into the game but ultimately they weren't good enough and Chelsea were fantastic".