Both sides were expected to make significant changes keeping in mind the explosive second leg that Old Trafford will be privileged to witness come Tuesday night. While Mourinho replaced almost his midfield and strike force, Sir Alex played it cautious as his squad missed only three players from the team that obtained a stalemate in Madrid two weeks ago. Rafael, Rio Ferdinand and Phil Jones were the notable absentees from the Red Devils' team as they made way for Chris Smalling, Nemanja Vidic and Antonio Valencia.
Sluggish United in the first half
Norwich manager Chris Hughton set out to frustrate United as he instructed his team to put as many men as possible behind the ball as he attempted to disrupt United's passing game. The league leaders huffed and puffed but always ran into a yellow wall and ensured that they would have to endure a lot of frustration.
Antonio Valencia managed to wriggle free on the edge of the penalty area and set up Rooney, who tried being a little too clever by exchanging touches with Shinji Kagawa only for the ball to be hacked clear, when he would have been better off shooting in the first attempt.
Robin van Persie, the season's top scorer looked increasingly out of his depth as he sent two efforts into the Stretford End of the ground. In the end it was his 'assist' that gave United a lead to take into the break. Valencia's cross was meant for the Dutchman but in his attempts to bring the ball down for him to make an effort at goal, he managed to deflect it to the path of Kagawa who made no mistake as he unleashed a volley with the outside of his right foot to give Sir Alex's side the lead.
Rejuvenated Norwich in the second half
After the break, United were expected to increase the tempo of the game up by a notch as they now had a lead to build on. Instead Norwich looked the more vibrant side with Robert Snodgrass giving Patrice Evra a hard time on United's left. With two men in Grant Holt and Anthony Pilkington to aim for, Snodgrass saw more of the ball in the second half and started troubling the United backline with his crosses.
It was a sign of Norwich's early dominance in the early part of the second half when possession stats attributed 68% to the Canaries while a measly 32% were for the home side. United were looking more susceptible in the air as Hughton's men pumped in cross after cross.
Fans had their hearts in their mouths when Grant Holt leapt higher than Patrice Evra to set up Snodgrass who had an empty goal to aim but blazed it over the bar. The goal, had it been scored, would have not counted as the referee pulled play back as they adjudged that Holt had fouled Evra in the buildup to the effort.
Welbeck for Van Persie changed the game
Robin van Persie's poor afternoon continued when he was left frustrated when Wayne Rooney chose to go for goal when the Dutchman felt that the England striker should have passed to him. That was the former Arsenal man's last action of the game as he was hauled off for Danny Welbeck. The youngster's introduction allowed Kagawa to move into a more central role playing just off Wayne Rooney.
10 minutes later, Sir Alex brought on Tom Cleverley for Anderson as he looked to inject some pace. The effect was instantaneous as suddenly the Red Devils were looking more lively. The changes paid off as Rooney did well to set up Kagawa for his second of the day.
As Norwich were suddenly in disarray, United seized their chance when a sweeping move involving Welbeck, Rooney and Kagawa saw the former Borussia Dortmund man complete his hat-trick with a chip over Canaries keeper Mark Bunn.
Even though the tie was done and dusted, there was still time for Wayne Rooney to add the icing on the cake with a fierce shot outside the box that gave Bunn no chance.
Mourinho will be more happy than Sir Alex
Yes, United won 4-0, but it must be seen that Sir Alex had chosen not to tinker with the team that started in Madrid two weeks ago even though the opposition were Norwich City. Jose Mourinho on the other hand retained only four players, from the team that drew against Manchester United at the Bernabeu namely Diego Lopez, Sergio Ramos, Fabio Coentrao and Rafael Varane, against Barcelona in their La Liga tie.
Despite the massive change Real Madrid ran out winners against a Barcelona side who have won only one of their last four games. While United laboured to break down the Canaries with a majority of their first team, the Galacticos proved that their formula to tackle Barcelona's passing game was indeed effective despite not having their first choice XI.
This will be a massive shot in the arm for Jose Mourinho as he takes his team to England to ensure a passage into the quarter-finals as he chases the elusive 'La Decima'.
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