Arsenal continued to bang in the goals with a 3-1 home victory over Birmingham City while Tottenham Hotspur survived a 60th-minute red card for Jermain Defoe to secure a 2-1 win at Portsmouth.
Champion United leads the way with 22 points from nine games. Chelsea is second on 21, Spurs has 19 and Arsenal has a game in hand on 18 points. Manchester City, which was at Wigan Athletic yesterday, has 16 points, the same as Villa and Sunderland.
Liverpool's hopes of a first title in 20 years already look slim after a fourth defeat in nine league games, though it was furious Sunderland's controversial goal stood. The key moment came after five minutes when Darren Bent's shot cannoned in off a loose beach ball which had "Liverpool" written on it.
The visitors, without the injured Steven Gerrard and Fernando Torres, complained but Bent was happy to claim his sixth goal in five games.
Former FIFA referee Graham Poll told the BBC that according to the laws, play should have been stopped and a drop ball given.
"If that's the case then we've got away with one," Sunderland manager Steve Bruce told the BBC.
In Italy, Dejan Stankovic netted with a remarkable volley from the halfway line to help Inter Milan triumph 5-0 at Genoa to surge clear at the top of Serie A on Saturday.
Esteban Cambiasso, Mario Balotelli, Patrick Viera and Maicon also scored for Jose Mourinho's side.
Inter will be rejoined at the top if Sampdoria wins at Lazio but has opened a four-point gap over Juventus and Fiorentina, which drew 1-1 in Turin.
Juan Manuel Vargas put Fiorentina ahead on five minutes with striker Amauri tapping in his first goal since February to level for Juventus.