It looked like Manchester City had a point to prove against Manchester United on Sunday and their second-half performance was an emphatic statement to anyone who doubted them.
I saw this coming. It was always going to happen because the standards they have set have been nothing short of amazing, and they are still near the top of the league.
After seeing City lose one game, in the last minute, to Spurs, and then get a bit of luck against Everton, it was no surprise to see them come out for a huge game like a Manchester derby and absolutely batter United.
The way United collapsed at the City of Manchester Stadium was unacceptable, but you have to remember that they were playing against a team that has some unbelievably talented players and also possesses an amazing work ethic.
You can't only play for half a game against City.
I thought United did well for the first half-hour on Sunday.
They committed lots of men forward on the counter- attack and tried to win the ball back high up the pitch, which was quite impressive to watch.
It was a risky way of playing, but it was what United's fans wanted to see - their side having a go, and trying to be competitive in the game.
United caused City problems in the opening period, and had some decent chances.
When you take the game to City like that, their quality means you are going to give yourself chances when they break through your lines.
As the first half wore on, City had more and more possession and were up by two, but United still looked dangerous and were right in the game. It set us up for a great second half, but United didn't show up.
Their display after the break was disappointing because of their lack of concentration. It led to City scoring their third goal, and it was the same with many other chances they gave away. At key times, their players switched off.
They were worse off seeing their reaction after they went 3-1 down. They didn't have the desire to get back into the game or even have a go at City.
I don't know if that was down to complete fatigue because of who they were playing against, or if it was a demonstration of their lack of belief.
Either way, United capitulated after losing the game. They had nothing left to give and it looked like they were done. It must be a real worry for Rangnick to see that happen.
Even before City scored their third and fourth goals, it felt like there was an inevitability about the result because of how dominant they had become.
It is hard to pick out individuals from a display like that because it was a collective effort from some wonderful players.
The work ethic of the two players in the middle of the pitch, to always get back and help their defenders, and then to also press and do all the other things you want from yourMidfielders, was just incredible.
City were really impressive going forward. Kevin de Bruyne was at his best and it was a pleasure to watch.
It is difficult to stop De Bruyne when he is on top of his game because you have got the attacking players around him that City do.
Again, Silva contributed in that way too, he set up their first goal, while Jack Grealish looked full of confidence, and the game went on.
I was impressed by Phil Foden's ability to understand the game in that area of the pitch and his ability to make a real impact.
It felt like Foden and De Bruyne were leading the attack for City.
We already know that the only team that can stop City retaining their title is the other team.
The game between the two teams will be a huge one, and will take place on 10 April.
There will be some twists and turns along the way, but I can't wait to see that one.
Football is not like that, and it is going to be interesting to see where the teams drop points over the next few weeks.
United has a lot of bigger problems.
United are not playing particularly well and they have a tough run-in with three games in hand, but they are above them and have three games in hand.
They are going to struggle against them because they still have to play them. It would be a huge shock for them to finish fourth and make the playoffs.
Danny Murphy was talking to Chris Bevan.