City meet Feyenoord in the Champions League tonight on the back of five consecutive defeats.
Guardiola said of the make-up of his squad: "It depends on the performance. There are players who are 30 years old and older who perform incredibly well. There are players who are 23 who perform poorly. I don't look at age. All teams have players of certain ages.
"My own analysis is not that we don't get results because we have players over 30 years old. Because a few weeks ago they were the same age and we won the Premier League, reached the FA Cup final and were eliminated by Real Madrid in the quarter-finals of the Champions League.
"I want to defend what we have done because I know these guys and I never blame one player.
"There are many factors that make a difference. If I could say what the reason was, I would solve it immediately, but it is not that simple."
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