This was devastatingly brilliant from Manchester City and simply devastating for Sunderland.
On paper this was a cup tie between two teams in the same division, in reality they are playing at completely different levels. City's progress into the last 16 of the League Cup was so easy, it looked almost cruel.
City may have had a couple of setbacks, at home and in Europe, but it is ominous how easily they destroyed Sunderland, on the road, in a competition they do not really care about.
The Black Cats clearly have problems - they are bottom of the table and have not won a league game since May; and this was almost as strong a side as manager Dick Advocaat can name.
He did not throw in the towel and pretend the league was more important before a ball was kicked, but his team were sliced open early and then torn apart as City scored four times before half-time.
It is debatable if City can put out a weak side given the quality of their squad, but few expected them to put out a team as strong as this given the League Cup is fourth in their list of priorities this season.
City's starting line-up cost £247.7m, Sunderland's added up to roughly £45m. Sunderland, though, have had an excellent home record against City, a run of four consecutive victories coming to an end last season.
Perhaps Manuel Pellegrini had that in mind when he decided who would travel to the North East. Then again, maybe this was the manager's way of punishing his stars for losing at home to Juventus in the Champions League.
City went in front after nine minutes and had cruise control on just past the half-hour.
Sergio Aguero had already had two half-chances, failing to convert a cutback from Jesus Navas before poking another effort wide, when he put City in front from the penalty spot. Not for the first time this season, Sunderland's left-back Patrick van Aanholt made the error, clattering into Navas. Aguero did the rest.
Fabio Borini thought he had equalised, but the referee Roger East pulled play back, rather dubiously, for a foul on Nicolas Otamendi.
Sunderland went close when Ola Toivonen's header was tipped over by Willy Caballero, but City's response was crushing, sweeping forward from the resulting corner to play in Kevin de Bruyne, who drilled a shot inside the near post.
It looked like it was game over moments later when Raheem Sterling's shot came back off the post, but still found its way into the net off the back of goalkeeper Vito Mannone.
And it was when Sterling was far more clinical, played onside by Van Aanholt and steering a shot inside the far post from a tight angle.
The second half was largely meaningless, even if Sunderland restored some pride by preventing the visitors from scoring again, and pulled one back through Toivonen.
Carry on like this, though, and the Wearsiders really will be in a different division to City next year. (© Daily Telegraph, London)