Aguero played 39 times in all competitions and scored 30 times last season. Not sure I would say he's on the decline
He said in an interview recently that after the surgery on his knee this is the first time he has been able to move it without pain in five years. I was very much of the opinion he was on the way out last summer, in a similar way to potato face, peaking so strong so early in your career sometimes means you decline earlier - and he has well and truly proved me wrong. If that was playing through pain I can imagine we might be about to see an even better season for Kun.