In 2003 he advanced to the second round of the Dubai Tennis Championships, where he lost to Roger Federer, and the MercedesCup, where he defeated Antony Dupuis before being eliminated by Rainer Schüttler.
In 2012, Kern was again awarded a wild ward into the main draw of the MercedesCup, where he lost to Thomaz Bellucci in the first round.