Neville says Suarez didn't help his case by falling theatrically to the ground.
"The problem is Suarez threw his head back and he didn't need to do that," he told Sky Sports.
"The referee thinks it's an unnatural movement and it's too much. That's his problem. I think it was a penalty.
"United's one is a penalty for me. The mistake Liverpool made is that Agger and Johnson should have taken Valencia out [on the half-way line]. That might sound a little bit cynical, but that's football unfortunately.
"Then Glen Johnson tackled from the wrong side. He's clipped his heel, there's a push in the back and Mark Halsey had no option other than to give a penalty."