The 32-year-old hitman announced earlier this week that he would be moving to the Stadio Olimpico when the January transfer window opens, but Bayern have now made the transfer official.
A statement reads: "FC Bayern gives its player Luca Toni (32) on loan to Roma until 30.6.2010. An agreement between AS Roma and Bayern has been reached."
It is a return to Serie A for Toni after he left Fiorentina for Bayern in 2007. The World Cup winner was prolific in his first one-and-a-half seasons in the Bundesliga, but struggled badly in 2009.
Following the arrival this season of coach Louis Van Gaal, whom Toni did not see eye-to-eye with, an exit seemed inevitable due to a lack of playing time.
Toni will be hoping that his link-up with Francesco Totti in Rome will earn him a recall to the Italy national team in time for the summer's World Cup in South Africa.
Anthony Sormani, Goal.com
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