Wayne Rooney was bought a guitar for his 22nd birthday last week, but the Manchester United forward will be hard pressed trying to strike a chord as sweet as his partnership with Carlos Tévez is at the moment.

Middlesbrough were the latest team to suffer at the feet of this intoxicating alliance and if the pair continue to wreak havoc in opposition defences over the course of this season and beyond, Sir Alex Ferguson’s belief that they could come to form “the complete partnership” may be realised.

After a few teething problems, Tévez and Rooney’s past seven matches together have yielded ten goals. It is a remarkable return, given that only a matter of weeks ago people were wondering whether they could play together while championing the importance of Louis Saha. If he can regain his fitness, Saha could have a crucial role to play this term, but such is the bond that Rooney and Tévez have formed, the France striker is in danger of becoming a forgotten man.

Rooney and Tévez have spent only 550 minutes on the pitch at the same time, but the understanding that has been increasingly apparent in recent matches appeared almost telepathic on Saturday, not least when they combined for a wondrous third goal.

When quizzed about his partnership with Tévez before the Champions League match at home to AS Roma at the beginning of the month, Rooney appeared unconvinced that it could work, but those misgivings have given way to a gleeful acceptance that his game is benefiting as a result.

“I’m feeling better and sharper with each game,” the England forward said. “With Carlos coming in, I’m playing like an old-fashioned centre forward. I’m not getting as involved in the build-up play and I’ve started to score ‘easy’ goals, which I’ve never really done.

“Carlos is brilliant and intelligent, playing just in behind the opposition’s midfield. That is where I like to play as well, but I feel as if I can change my game for whoever I play with now.”

With Arsenal to play in their eagerly awaited meeting at the Emirates Stadium on Saturday, United have hit their stride at the right time. By scoring four times for the fourth game in succession, United equalled a 100-year-old club record on an afternoon when positives abounded.

Nani, whose 30-yard thunderbolt got the ball rolling, and Anderson are starting to justify their transfer fees, while the return of Owen Hargreaves after almost two months out with tendinitis of the knee was, in many respects, the most pleasing aspect of this victory. United look a far more robust team with Hargreaves playing.

Middlesbrough were not nearly as bad as the scoreline suggests and it was ultimately two mistakes by Stewart Downing in the space of nine minutes in the first half that swung the game in United’s favour. Having headed Tuncay Sanli’s divine cross wide when he should have scored to give his team a 2-1 lead after Jérémie Aliadière’s first league goal for five years had drawn Middlesbrough level, Downing made a mess of things when he attempted a “Cruyff turn” in his own penalty area and allowed Nani to divert the ball to Rooney, who applied an emphatic finish.

There was nothing fortunate about United’s third, though, with Rooney teeing up Tévez with a deft backheel to complete a fine, sweeping move, or the fourth, when the Argentinian was played in after another explosive run from Rooney.

“I think we have got great balance all across the pitch,” Hargreaves said. “We have got great options, so whatever you want to do, however you want to play, we can do that against any team.” Arsenal, watch out.

How they rated

Manchester United (4-4-2) E van der Sar 6 W Brown 7 R Ferdinand 6 N Vidic 6 J O’Shea 6 C Ronaldo 6 O Hargreaves 8 Anderson 7 Nani 8 C Tévez 7 W Rooney 9 Substitutes D Fletcher 6 (for Hargreaves, 66min), G Piqué (for Ferdinand, 73), R Giggs (for Anderson, 78) Not used T Kuszczak, D Simpson

Middlesbrough (4-4-2) M Schwarzer 6 L Young 5 J Woodgate 6 D Wheater 6 A Taylor 5 G O’Neil 6 L Cattermole Y 7 F Rochemback Y 4 S Downing 5 J Aliadière 6 Tuncay Sanli 7 Substitutes B Hutchinson 5 (for Aliadière, 56), Lee Dong Gook (for Tuncay, 80), G Boateng (for Cattermole, 90) Not used R Turnbull, S Hines