The German Football Association (DFB) has informed via its official webpage that Mainz defender Leon Balogun is being investigated for violent conduct that took place during the Bundesliga tie against Eintracht Frankfurt at the Commerzbank-Arena on Sunday.<br /><br />Referee Felix Zwayer did not take any action after the Nigeria international apparently hit Carlos Zambrano with his right knee in his stomach, with television images confirming that he committed the offense.<br /><br />The DFB has queried Balogun regarding the incident and he could be suspended for some games if his statement does not hold water.<br /><br />Since the 2008-2009 season, the Mainz number three has been yellow-carded 35 times and was dismissed while defending the colours of Fortuna D&uuml;sseldorf II against <span>Rot-Wei&szlig; Oberhausen on October 6, 2012.</span><br /><br />Ifeanyi Emmanuel<br /><br />