WAYNE Rooney and Juan Mata both scored twice as Norwich City were comprehensively beaten 4-0 by Manchester United at Old Trafford.
After the Canaries matched their opponents for the majority of the first half, Steven Whittaker's foul on Danny Welbeck four minutes before the break gave United a penalty that Rooney converted.
The England star then curled in from range after half-time to double the hosts' lead, before Mata came off the bench to net a brace of close-range finishes that earned Ryan Giggs a comfortable triumph in his first game as manager.
Norwich struggled to trouble David de Gea throughout, going closest through Martin Olsson in stoppage time as he hit the bar with a deflected shot from distance.
With just two games of the Premier League season remaining, City are now just a point clear of the relegation places and will be drawn into the bottom three if Sunderland's game with Cardiff City on Sunday's doesn't end in a draw.
Ricky van Wolfswinkel was named in the starting eleven at the expense of Gary Hooper before kick-off, while Giggs made six changes that included the demotion of Mata to being among the substitutes.
The entire Old Trafford crowd was on their feet to welcome their new boss before kick-off, but the 2000-strong corner of Canaries supporters, which included City winger Elliott Bennett, were making their voices heard in the early stages.
They thought their team had taken the lead on nine minutes after Jonny Howson smashed home from inside the box, but a free-kick was given to United for a push by van Wolfswinkel on Phil Jones in the build-up.
The hosts’ first chance came when Danny Welbeck found himself in space at the back-post on 14 minutes after Martin Olsson’s headed clearance, with John Ruddy
having to be firm in pushing his drive wide of the post.
Giggs’ team were having to be patient in possession with Norwich maintaining their structure to good effect, restricting to them to half-chances like when Shinji Kagawa poked wide at the back-post from Jones’ deep cross and Ruddy reacted quickly to Antonio Valencia’s low shot.
That was until the 40th minute, when Welbeck fell easily under the challenge of Steven Whittaker in the box, although City will be frustrated that they didn’t deal with the weak cross that came into the box.
Rooney sent his England teammate Ruddy the wrong way from the resultant penalty to give United a lead they barely deserved and which came as a relief to an increasingly agitated home crowd.
HALF-TIME: Manchester United 1-0 Norwich City
Neither side made any changes at half-time, but United carried their momentum into the second period and Rooney got his and his team’s second goal three minutes in.
The forward picked up the ball in a seemingly unthreatening position from Kagawa on the left, but he was allowed to stroll in field and curl an effort that beat the stretching Ruddy, with the ball going in off the post.
With the bit between their teeth, United pushed for a third and Ruddy made an excellent save to deny Welbeck before Nemanja Vidic headed over at the back-post from the subsequent corner.
Robert Snodgrass’ free-kick forced the first save from David de Gea on 59 minutes, but City needed to find the net quickly if they were give themselves any chance of getting back into the game.
Their task became almost impossible, however, when substitute Mata pounced just three minutes after coming on.
Valencia fed Jones on the right, and the Spaniard connected with his swinging cross with a well-timed volley into the net.
Bradley Johnson’s ambitious effort from distance trickled wide was only a precursor to United’s fourth on 73 minutes, and it was another poacher’s effort from Mata.
Valencia met Patrice Evra’s cross with a volley at the back-post, and Mata was brave enough to meet the ball with his head before any Canaries defender, nodding it home.
Johan Elmander, who had made an impact since his introduction as a substitute, robbed Rooney of the ball up the other end and almost managed to find the bottom corner with a low shot, but in truth City’s attacking forays had been blunt all afternoon.
Rooney tried to lob Ruddy to complete a stylish hat-trick but his effort landed on the roof of the net, before another of Johnson's hopeful efforts from range forced a save from de Gea.
Olsson then went one step closer as his shot came off Jones before looping over de Gea yet off the bar, before Javier Hernandez squandered a chance for the hosts in the final moments.
FULL-TIME: Manchester United 4-0 Norwich CityGOALS
: Red Devils
: Wayne Rooney (pen 41, 48), Juan Mata (63, 73)
: De Gea; Jones, Vidic (c), Ferdinand, Evra; Valencia, Carrick, Cleverley (Hernandez 71), Kagawa (Young 65); Welbeck (Mata 60), Rooney. Subs not used
: Lindegaard (GK), Smalling, Nani, Fletcher.
: Ruddy; Whittaker, Martin (c), Turner, Olsson; Johnson; Snodgrass, Howson, Fer (Tettey 80), Redmond (Hooper 69); van Wolfswinkel (Elmander 57). Subs not used
: Bunn (GK), Gutierrez, R Bennett, Josh Murphy.
: Lee Probert