SaturdayBremen     vs     FC Augsburg    16:30 Hamburg SV     vs     SpVgg FuDortmund     vs     Hannover 96Nurnberg     vs     SC FreiburgWolfsburg     vs     Schalke 04Leverkusen     vs     Stuttgart    19:30 SundayHoffenheim     vs     Bayern        16:30    F Düsseldorf     vs     Mainz        18:30    BERLIN – Swirling speculation surrounding the future of Borussia Dortmund striker Robert Lewandowski has angered coach Juergen Klopp ahead of Saturday’s Bundesliga clash against improving Hanover 96.Lewandowski, whose Dortmund contract runs out in 2014, has so far refused to sign an extension and has been linked with a move to rivals Bayern Munich, who currently lead the title race by 17 points. Media reports suggest Lewandowski could delay a move until 2014, so he could he could join Bayern without a transfer fee, while the player said this week he would see out his contract at Dortmund."Why don’t you ask me about (Bayern strikers) Mario Gomez and Arjen Robben and where they will be playing next season,” Klopp told reporters. "We could be talking about other things as well."I can understand that people make a big deal out of it but for us it is a normal situation. We will not get stressed out by this. Robbi is with us.Champions Dortmund are looking to bounce back from Wednesday’s 1-0 German Cup quarter-final defeat to Bayern and are eager to hold on to second place in the Bundesliga.It was Dortmund’s first defeat in seven games to Bayern and means they realistically have only the Champions League left to play for.