Jürgen Klopp will return to Borussia Dortmund’s stadium for the farewell game of Lukasz Piszczek and Jakub Blaszczykowski, the Bundesliga club said on Friday. The former Dortmund boss will coach Blaszczykowski’s team in the friendly game on September 7. Former Dortmund players are also to take part in the celebration. “I’m really looking forward to it,” Klopp said. Klopp served as Dortmund coach from 2008 and 2015, and led the team to the Bundesliga title in 2011 and 2012, as well as to the Champions League final in 2013. He moved to Liverpool in 2015, but announced his departure from the Prem…