Sam, an attacking midfielder who usually plays on the wing, agreed to a four-year deal effective July 1, reports Xinhua.
The 25-year-old has seven goals and five assists for Leverkusen in the Bundesliga this season. In all, he has 23 goals in 83 league games since switching from Hamburger SV in 2010. He previously spent two seasons on loan at Kaiserslautern.
Sam made his debut for Germany in a friendly against Ecuador in May, going on to make five appearances for the national side.
--IANS (Posted on 08-01-2014)