The Brazilian defender had been expected to see his first-team opportunities limited this term but is now likely to pen a contract extension beyond the summer of 2014
The Brazilian defender made just 17 appearances for the Bavarians in all competitions last season and it was expected that he would see little game time following the arrival of Pep Guardiola as coach during the summer.
However, Sammer has little doubt that Rafinha, who has already played 22 games this term, will extend his current contract, which expires at the end of the current campaign, revealing that the right-back has impressed all and sundry at Bayern with his attitude and work ethic.
"Rafinha accepted his role and is a totally positive spirit," the former Germany international told Kicker. "He fits wonderfully in this group.
"He has also developed in a sporting sense [this season], so his renewal is self-evident."