Gerrard's strikes either side of halftime put the visitors in control and Luis Suarez sealed only Liverpool's second win at Old Trafford in nearly 10 years with a well-taken third.

Skipper Gerrard could have completed a rare hat-trick of spot kicks but struck the post after Nemanja Vidic was red-carded for tripping Daniel Sturridge shortly before Suarez completed the rout.

Gerrard's first penalty after 33 minutes followed a deliberate handball by Rafael that could have earned the defender a second yellow card, while his second shortly after the break was for a clumsy Phil Jones challenge on Joe Allen.

United's afternoon went from bad to worse when Vidic sent Sturridge sprawling in the area with a lunging tackle and though Gerrard could not beat David de Gea for a third time Suarez's neat finish after 84 minutes capped a dazzling Liverpool display.

Defeat left United languishing in seventh place with 48 points, 11 adrift of fourth-placed Arsenal who are in action later on Sunday at north London rivals Tottenham Hotspur.

Chelsea see red

The race for the Premier League title was blown wide open when leaders Chelsea had two players sent off in a 1-0 defeat at Aston Villa on Saturday.

Chelsea also had manager Jose Mourinho sent to the stands in stoppage time as the match exploded into life in the last few minutes but the normally loquacious Portuguese bit his tongue after the game.

“I prefer not to talk,” he told Sky Sports television. “If I talk I will bring the game into disrepute and I don't want to be in big trouble.”

Mourinho was clearly unhappy Brazil midfielder Willian was sent off by referee Chris Foy for a minor shoving offence, his second caution, in the 68th minute -- a decision that played a key role in deciding the outcome of the match. Fabian Delph’s clever 82nd-minute backheel secured Villa’s victory.

Chelsea have 66 points with eight matches to play while City are on 60 with 11 games remaining.

Chelsea’s second red card was handed to Brazil midfielder Ramires in stoppage time for a two-footed stamp on Karim El Ahmadi that Villa manager Paul Lambert described as “a leg-breaker”.

The other results on Saturday had more of an impact at the wrong end of the table and left the bottom nine clubs separated by seven points, from West Ham United in 12th place on 31 points to basement side Fulham (24).

West Ham United lost 3-1 at Stoke City while Fulham won for the first time since New Year's Day and for the first time since German Felix Magath took over as manager on February 14.