The Bulgarian should have had another goal after half-time but, after Darren Fletcher had doubled the Red Devils' advantage shortly before the break, it was evergreen substitute Ryan Giggs who extended his remarkable record of scoring in every Premier League season when he latched on to Paul Scholes' inspired pass and sent a first-time volley bouncing past Steve Harper.
It was part of another masterclass from man-of-the-match Scholes, who with every game must make Fabio Capello cringe at his failure to lure the 35-year-old out of international retirement for World Cup duty in the summer.
The only real disappointment for United was another blank day for Wayne Rooney, who has now gone 13 matches for club and country since he last scored, against Bayern Munich in March.
Questions will continue to be asked of Rooney until he starts to show the form that established himself as one of the world's leading players last season.
His performances in South Africa were almost too bad to be believed, the nadir coming in England's terrible draw against Algeria in Cape Town.
Yet at times, it almost feels as though Rooney is trying too hard.
His work-rate remains impressive but too often shots are snatched.
He succeeded only in battering a free-kick into the Newcastle wall with one obvious opportunity, then skied Berbatov's nod-back high over the bar when far better was expected.
Even his part in United's second goal was accidental as he failed to control Patrice Evra's low cross and succeeded only in prodding the ball towards Fletcher, whose smart turn and finish brought an admiring nod of approval from the unselfish England man.
Since his club record £30.5million arrival from Tottenham, Berbatov has often found himself as the man being sacrificed by Sir Alex Ferguson in the biggest United games.
With Javier Hernandez threatening to take Old Trafford by storm and Michael Owen's lack of match practice costing him a place on the bench, Berbatov knew he must start to impress on a more consistent basis.
He certainly showed Rooney the way to goal when Antonio Valencia showed admirable determination in getting back to win possession for his team which John O'Shea quickly moved forward to Scholes.
The old master wasted no time in pushing the ball towards the Bulgarian, who was marginally onside and profited further when Jose Enrique nudged the ball further forward as he attempted to tackle.
Berbatov steadied himself before drilling a shot from an acute angle into the far left corner.
It was the first harsh lesson of top-flight life for Newcastle, who surprised many, including Ferguson, by bouncing back from the Championship quite so soon.
Young striker Andy Carroll was one of the majorfactors in their promotion.
But after getting away from Nemanja Vidic with a superb run across the United box, he should have buried Joey Barton's corner instead of nodding a golden chance to put Newcastle ahead tamely wide.
Later, with the points effectively secure, United set about boosting their goal difference.
Rooney may be struggling to locate the net but there was plenty to be admired about his delicate touch to find Berbatov after Scholes had played the initial bullet pass.
It was a better chance than the one Berbatov had converted earlier. Again he beat Harper, but this time also put the ball wide of his left-hand post.
For Rooney, it was his last meaningful involvement before he was replaced by Hernandez.
At least he is another hour closer to the 600 minutes of playing time Capello thinks he needs to achieve top form, although the process would surely be accelerated if he could find the net.
Anything would do, including the bizarre one off his face that Hernandez managed in the Community Shield.
That goal ensured the Mexican was not searching for his first competitive goal as he chased about.
But it was the tracer-bullet accuracy of Giggs that proved to be the difference late on after he had been picked out by his old friend Scholes.