The Wheels on the Chelsea Bus go round and round, round and round. That is, of course, until Manchester United ended their 40 game unbeaten run at Old Trafford on Sunday with a Darren Fletcher header.
There can be no doubt judging from his body shape and his position in the box that Fletcher was trying to square the ball. But as it was the ball looped over Petr Cech and John Terry and into the net to spark wild celebrations.
Cue the parallels with the end of Arsenal's 49 game unbeaten run at Old Trafford, with events coming full circle and United beating the latest dominant Premiership champions. However, this comparison is only superficial.
Despite the obvious 'league leaders defending a long unbeaten run' thing, there are few similarities. United's battling spirit was certainly evident in both games, and their pressing of the opposition squeezed the life out of both Arsenal and Chelsea's midfield.
The phenomenal crowd support was also in evidence. The United fans roared on their side, baying for victory against the team that threatens to overtake United's footballing and commercial dominance much more than Arsenal ever have.
Also, United were given the task once again of showing the rest of the Premiership that a so-called 'unbeatable' side were fallable.
But there the on-pitch similarities end. Against Arsenal, United were extremely physical. They roughed up Jose Antonio Reyes, and out-muscled an Arsenal side who recoiled in the face of its rival bearing too many teeth. United were borderline excessive that day; on Sunday they were nowhere near.
The difference was that their will-to-win was greater than it had been in any other game this season. They would not be denied - a strong mindset that Roy Keane would have applauded. Each player applied himself to the task appropriate to the day, and no-one embodied this more than Wayne Rooney.
Sunday was not a day for Rooney's trickery and guile - he had to work tirelessly for the team, to make sure they pressed Chelsea as high up the pitch as they could. And he did. It was a very focused and mature performance from a player on which so much of United's future rests.
Arsenal never pressed for long periods at Old Trafford as Chelsea did in the last half hour on Sunday. United could not hold onto the ball and, partly as a consequence of inexperience, began defending deeper and deeper inviting Chelsea pressure.
This was not the case 13 months ago. While United did not create a plethora of chances, they did minimise Arsenal to the counter attack. That was the only danger to a United side whose ball retention was much better than it was on Sunday. It has been a while since I have seen a United side hang on to a 1-0 lead like that at Old Trafford.
But it is worth noting that United needed to produce a battling display as much to convince the fans that the hunger was still there. United's limp displays at Middlesbrough and Lille had their foundation in games earlier in the season, like the fortuitous wins at Sunderland and against Benfica at Old Trafford.
The similarity that should be recognised is that United's Premiership role is in danger of becoming demoted. For more than ten years, United have been the side that everyone wants to beat; they were other side's Cup Final, and they raised their game accordingly. This is still true to a great extent, of course, but the fear that used to be accompanied with playing the Red Devils has steadily eroded over the last couple of seasons.
The lifeless Middelsbrough display and the Chelsea win were so alarmingly diffrent that the United players have to prove they are not becoming just a difficult away game for the big two. If they only raise their level for the big games, they are in danger of parodying the sides that played them in the last decade.
This criticism could also be true of the fans - Old Trafford is often a 67,000 capacity morgue on days when 'lesser' sides show up at Old Trafford.
If the performances prior to the Chelsea game are repeated, United will become like Chelsea under Claudio Ranieiri - a side with nearly all the component parts to make champions, but lacking the fight over a 38 game assault.
That is their biggest test. An estimated 750 million people world-wide tuned into watch the United-Chelse game. Far less will watch United's trip to Charlton in two weeks' time, but the game is as important to their title hopes as beating Mourinho's men. United beat Arsenal and then lost to Portsmouth. The players owe it to their great performance yesterday not to repeat that failing.