The 34-year-old is confused as to why the newly appointed Bavarians boss has opted to deviate so far from the template for success which the former coach had left behind
The former Barcelona coach failed to secure his first piece of silverware since being appointed at the Allianz Arena earlier this summer, with arch-rivals Borussia Dortmund running out 4-2 winners in the DFL-Supercup last Saturday.
And Pizarro, who was apart of the club's historic treble-winning team last season under Heynckes, says he is shocked to see Guardiola alter what was a tried-and-tested formula for success.
He told reporters: "I have never seen a coach change so much."
Meanwhile, Arjen Robben - who netted the club's winning goal in the Champions League final in May - has hinted that the Spaniard could perhaps aim to keep things simple.
He added: "You don't have to make football more complicated than it is."
The Bavarians secured the Audi Cup with a 2-1 victory over Manchester City on Thursday, and now prepare for the DFB-Pokal first round clash against Schwarz-Weiss Rehden and their Bundesliga opener at home to Borussia Monchengladbach.