The ex-midfielder, who started his career at Old Trafford, believes that United are 'a long, long way away' from troubling Chelsea or Liverpool in the Premier League title race, but singled out one the Red Devils' biggest names for criticism.
Dunphy, who also criticised Wayne Rooney, believes that new manager Jose Mourinho is doing a better job than predecessor Louis van Gaal, but that United still are not back to their best.
"Since Van Gaal left and Mourinho took over they’re having a go, there’s no doubt about that," Dunphy told 2fm .
"But I’d say they’re a long, long way away from where they would need to be to trouble the likes of Chelsea, who gave them a hiding a few weeks ago, or Liverpool, who I think will give them a hiding whenever they play them again."
Mourinho's side failed to close the gap between themselves and the top four on Saturday as Arsenal came from behind to snatch a late draw, with Pogba's performance provoking the ire of the Irishman.
"It was a spirited performance, but in the end they gave up a soft goal," the former Millwall midfielder said.
"David de Gea had nothing to do all afternoon, but for the goal the full-back walked past Marcus Rashford.
"Paul Pogba should have been giving him cover, he didn’t bother, he just stood there because he doesn’t really understand the game.
"The ball was crossed to the far post and Olivier Giroud had a simple task. It was a very bad goal to give away."