Manchester United have reached such an exhilarating run of form that the biggest and most blase crowd in English football could even slip out of habit and celebrate a home win for Chelsea when the results flashed up on Old Trafford's scoreboard.
The cackling was predominantly schadenfreude at Manchester City's expense, but it also confirmed that, post-Jose Mourinho, the supporters of Sir Alex Ferguson's team have come to regard the deposed champions with a mixture of disdain and curiosity rather than the fear of old.
The focus at Old Trafford has shifted towards Arsenal rather than Chelsea, with Ferguson talking about a return to "old times" in the contest for supremacy at the top of the Premier League. Arsenal, he believes, are the most credible challengers to his winning a 10th championship in 15 years, but one certainty is that he will not view Saturday's trip to the Emirates Stadium with any trepidation. Ferguson's team, who welcomed back Owen Hargreaves for only his fourth game since joining the club in the summer, seem immune to insecurity and it is beginning to feel like a trick of the mind that their fans were getting agitated earlier this season about a lack of entertainment.
The oddity was that Ronaldo, though frequently eluding his opponents and showing his usual desire to take possession of the ball, played only a peripheral role. The Portugal forward, usually Middlesbrough's bete noire, did not play any part in the goals but it scarcely mattered because, collectively, United were at their very best and it was one of those days when Rooney's performance could have been set to music - from a Middlesbrough perspective, possibly the theme from Jaws.
The most impressive aspect was that the performance of Gareth Southgate's team was far from the worst put up by an away side at Old Trafford over the last year or so and, at times, the visitors put together some attractive football of their own.
Southgate's boldness will be applauded by purists and it was difficult not to sympathise when he explained afterwards that he wanted to stick to his beliefs - namely, open and attacking football -rather than taking the popular approach of visiting managers to Old Trafford by packing midfield and deploying a lone forward. The reality, however, was that his system gave Middlesbrough's opponents the time and space to work their elaborate, triangular passing moves. Adventurousness can only be applauded when it is accompanied by common sense and, in this case, Southgate was badly misguided.
Rooney, in particular, made sure that was the case and, as he approaches the point of maximum expression, how preposterous it may feel over the coming months that Euro 2008 is likely to go ahead without the assassin-faced baby as one of the star turns.
His performance here combined brute force, beautiful subtlety and, above all, a desire to make things happen, the highlights being an inch-perfect 60-yard pass to Ronaldo, the backheel (with his left foot) that set up Tevez to make it 3-1, and the bull run from inside his own half before the Argentinian finished the scoring with a shot that deflected off Andrew Taylor and looped into the net.
Rooney also scored his eighth goal in his last seven games, lashing his shot beyond Mark Schwarzer after a ghastly mistake by Stewart Downing, and it speaks volumes for the England forward that his performance should be the main talking point when Nani, with a swivel of the hips and a rasping 30-yard drive, had bewitched Old Trafford with the stunning quality of his opening goal. Nani has a tendency to disappear for long spells but he also has a wonderful knack for finding the top corner. After a winding run beyond Gary O'Neil, Luke Young and Cattermole, his goal will rank among the finest witnessed inside this stadium in the Ferguson era.
The Telegraph
Gareth Southgate stood amid the munificent opulence of Old Trafford as he surveyed the damage inflicted on his Middlesbrough team, and came out with the understatement of the season. "I think they've probably got more attacking options this year," he said.
Manchester United's attacking options start with the throwing arm of Edwin van der Sar, and continue through every fibre and sinew of the 10 men in front of him. They even scare teams when Ryan Giggs warms up on the touchline, or Louis Saha shifts position in his seat in the stand.
For around half an hour Middlesbrough just about lived with United and might even have gone ahead had Stewart Downing's header been a foot to the left. Then the floodgates opened.
If it wasn't Nani performing like a slighter Cristiano Ronaldo on the left, it was the real thing on the right; or else it was Wayne Rooney and Carlos Tevez carousing through the centre. Anderson probed just behind and Owen Hargreaves anchored midfield and sprayed the ball around. It was magnificent stuff.
"We could have scored a lot of goals," Sir Alex Ferguson said of the second-half battering given to Middlesbrough. The partnership of Rooney and Tevez has taken to new heights the art of slicing through teams. Rooney made two goals for the little Argentine. Tevez tried to repay the debt, but Rooney blasted over when well placed.
If there was a moment that epitomised the understanding the pair have developed in a very short space of time, it was United's third goal, early in the second half. Tevez volleyed Anderson's chipped pass into the area for Rooney who, despite moving away from goal, managed to backheel the ball for Tevez, whose run into space had not been picked up. The finish was simplicity itself.
"The best way to play football is pass and move," Rooney said, "and as soon as Carlos gave me the ball I could see him starting his run out of the corner of my eye."
Ferguson said: "It was all about quick thinking, great vision and the courage to even try that. Wayne could have taken another touch, but he knew Tevez was making that run. It was a fantastic goal."
Tevez's second goal was all about the power of Rooney, first to shrug off the shirt-pulling attention of Fabio Rochemback on the halfway line, then to accelerate through the centre, before finding Tevez unmarked on the left of the penalty area. Tevez cut back on to his right foot before firing a shot that looped off Andrew Taylor and over Mark Schwarzer. The brilliance of Nani's opener was almost forgotten by the end.
Rooney's goal, set up when Nani nicked the ball off a dithering Downing, was routine by comparison. "We're playing fast, attacking football and that's the football I want to be involved in," Rooney said. "To play in this team is an honour."
The Times
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.
"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.
"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.