Rafinha has urged Bayern Munich supporters to be patient with Douglas Costa in his first season with the Bundesliga champions.
Bayern recently completed a deal with Shakhtar Donetsk to sign the attacking midfielder on a five-year deal, and Rafinha believes that his fellow Brazilian will need time to find his best form in Germany.
"Douglas Costa is a quality player, but with all due respect to the Ukrainian league and Shakhtar, Bayern are a different world, and Bundesliga opponents are better, more dynamic, more physical and quicker," the defender told the club's official website.
"He'll spot that straight away. We'll certainly have to give him time to settle in."
Costa made over 200 competitive appearances in his six seasons with Shakhtar.
