The Bremen old boy struck early in the second half after Theodor Gebre Selassie and Aaron Hunt had given the visitors the lead, with Bastian Schweinsteiger and Arjen Robben joining first-half goalscorer Franck Ribery on the scoresheet on a topsy-turvy afternoon in the Bavarian capital.
Gebre Selassie surprise
The game started in sombre mood as the two sets of players paid their respects to former FC Barcelona coach Tito Vilanova, who passed away on Friday following a long battle with cancer. Once under way, visitors Bremen made the brighter start and were celebrating after ten minutes, when Gebre Selassie burst into the box to sink his first goal in 52 top-flight assignments following an incisive breakaway.
As ever, Bayern were dominating in terms of possession, but were again struggling to serve up the decisive final ball. That all changed in the 20th minute, though, as Pizarro released Ribery, who raced away to net his eighth strike in 11 Bundesliga outings against the men from Bremen and thereby end a run of seven games without a goal.
Bremen on the Hunt
The contest followed a similar pattern until the visitors struck again on the counter thanks to a fantastic ball over the top from Franco Di Santo. Hunt still had it all to do, but made light work of Jerome Boateng before stroking into the net from close range. Santiago Garcia thought he'd made it three six minutes later, only to see the linesman's flag go up for offside.
Pep Guardiola responded by throwing on captain Philipp Lahm at the expense of Mitchell Weiser. The Bayern right-back was immediately afforded time and space to find Mario Götze, who could only guide the ball into the arms of Raphael Wolf. The Bremen stopper could do nothing to keep out Bayern's next effort, though, with Pizarro steering Thomas Müller's flicked header over the line from close range to level.
The champions were beginning to purr and it wasn't long before they had the points in the bag. Ribery's inventive back heel found David Alaba, who had the presence of mind to roll the ball into the path of Pizarro for his second of the afternoon, with Schweinsteiger heading home Lahm's cross for goal number four barely five minutes later.
Javi Martinez threatened a fifth, before substitute Robben added salt to Bremen's already gaping wound with a trademark run and left-footed finish from the edge of the box. Bayern inevitably took their foot off the gas as the game wore on, having rediscovered their scoring boots at just the right time ahead of Tuesday's UEFA Champions League semi-final second leg at home to Real Madrid CF.
Line-ups and statistics
Relive 's fantastic strike against Bremen courtesy of our official Bundesliga YouTube channel: