Robin van Persie's 15th goal of the season ensured Manchester United will spend Christmas Day on top of the Premier League tree as the Red Devils eased past Sunderland.
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Tom Cleverley's first league goal at Old Trafford and Wayne Rooney's fifth in four games were enough to keep United six points clear of neighbours City, with Fraizer Campbell's header against his old club scant consolation for the Wearsiders, who remain deep in relegation trouble.
Yet perhaps the most significant moment of the entire game came with Nemanja Vidic's introduction midway through the second half.
Plagued by injuries since August 2011, Vidic's absence during last season's run-in contributed to United's defensive wobbles and the Serbian is viewed as the main way of plugging the leaks that have been so obvious for a side who have still only kept three clean sheets all season.
Not for the first time, Sir Alex Ferguson used the build-up to offer support to an under-fire colleague, only for his team to dismantle them 24 hours later.
In ridiculing those who questioned Martin O'Neill's credentials, Ferguson was ignoring statistics that showed the Black Cats had won just twice in the Premier League this season, both on home soil against teams - Wigan and Reading - that are alongside them in the mire.
Within 20 minutes here, it had become apparent this was not going to be number three.
Ferguson had insisted those cheeky celebrations by Sunderland fans when the title was snatched away from their last-day visitors in May would play no part in the outcome.
Nevertheless, there was a sense of purpose about United's start which has rarely been matched this season.
Patrice Evra had already wasted one excellent opportunity when Ashley Young wriggled away from Carlos Cuellar close to the dead-ball line, then cut a cross back which Van Persie finished expertly.
Yet the goal also needed significant assistance from John O'Shea, who got himself into a muddle as he tried to clear Young's cross, which allowed Van Persie to profit.
Given Wes Brown's own-goal was the difference in last season's corresponding fixture, Sunderland's ex-United contingent have not had the happiest of returns to old haunts.
Within three minutes, the hosts had their second.
If Cleverley wants to assume the Paul Scholes mantle, he needs to start finding the net more consistently. And after two goals against Newcastle earlier in the campaign, the England man finally got his first in the Premier League at Old Trafford.
It was a gem too as Cleverley exchanged passes with Michael Carrick before drilling an excellent effort past Simon Mignolet from 12 yards.
With United scenting blood, Rooney wasted a glorious chance when he volleyed wide from Van Persie's knock-down.
The England striker then steered a near-post header wide from Evra's cross as the Red Devils threatened to run riot.
Half-time was approaching before Sunderland carved out their first meaningful opportunity, which Stephane Sessegnon struck Evra with before it flew over.
The interval introduction of Conor Wickham for the injured Steven Fletcher did trigger a flurry of activity around the United goal as David de Gea denied Craig Gardner and Sessegnon.
Yet the clear chances kept falling to the hosts. Rooney's shot rattled the bar after flicking off Titus Bramble, with Young blazing the rebound over.
Then, given the number of goals he has scored so far this season, came the somewhat surprising sight of Van Persie lobbing wide after Young had sent the Dutchman running clear of an over-stretched Sunderland defence.
There was little argument to be made for a Black Cats comeback and any pretence was ended just before the hour when an unselfish overlapping run by Van Persie was followed by a deft piece of skill that took him between Cuellar and Bramble before he set up Rooney, who tapped home from close range.
With victory assured, Ferguson felt sufficiently confident about easing Vidic back into the fray.
After only 13 appearances in a 16-month period that included a calf injury and two lots of knee surgery, the 31-year-old desperately needs to stay injury free in order to rediscover his old form.
Evidently, Vidic has plenty of work in front of him too judging by the uncharacteristic mistake that eventually led to United old-boy Campbell heading home from close range.