Frimpong is not the only Bundesliga star on Liverpool's radar ahead of the summer transfer window. The Reds are also interested in Eintracht Frankfurt’s Ansgar Knauff, Wolfsburg’s Konstantinos Koulierakis and Dortmund’s Nico Schlotterbeck, according to the report. Knauff is seen as a more versatile and cheaper option that Frimpong, with the Eintracht Frankfurt defender valued at €25m (£21m).