Aldridge wrote for the Liverpool Echo: "It's great to beat City but for the club we are, we shouldn't be worried about that. We should expect to beat them like we expect to beat Swansea.
"You go into the next game and sometimes as players you drop your guard, I've seen it so many times.
"I became disillusioned with football when I was Tranmere manager because of it. We could beat all the top teams in the Cups, all the first division teams, but come the next Saturday and we were rubbish. We couldn't get results.
"All the big games had a knock-on effect, it's what happens in football, it's a mental thing.
"The players just weren't at it, it was the worst performance since Tottenham and we've just got to get back on track.
"It was as if they just expected to win the game but you've got to earn that right and we didn't."