Gündogan hasn't featured for BVB since picking up an injury against FC Augsburg on the opening day of the season, and was sent home early from die Schwarz-Gelben's training camp in La Manga due to illness.
Out for "two or three games"
"As he's hardly featured during our preparations, his won't take part in the first two or three games [of the second half of the season]," said Klopp following Dortmund's friendly victory over 1. FC Kaiserslautern on Saturday.
Goals from , Jakub Blaszczykowski and FC Bayern München-bound Robert Lewandowski helped secure a 3-1 win over the Bundesliga 2 outfit at the Fritz-Walter-Stadion, with Marcel Gaus grabbing the only goal for the hosts.