German media claims the Peruvian has sealed terms with his former club, where he will act as experienced backup to first-choice center forward Mario Gomez next season.
The 33-year-old's prospective transfer to the Allianz Arena now looks to have been completed following months of speculation linking the two parties.
The publication states a secret meeting was held between the striker's agent Carlos Delgado and sporting director Christian Nerlinger to finalize the deal, with a medical already undertaken in advance.
It marks a return to Bayern for Pizarro, who played for the club between 2001 and 2007, scoring 74 goals in 171 Bundesliga appearances, before departing for an indifferent spell with Chelsea.
However, he returned to Germany with Werder after only one season, another of his former clubs, and has successfully rebuilt his reputation as a prolific finisher on the continent.
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