Foreign the (West) German national football team, he earned 19 caps and was in the squad for Euro 1992. Frontzeck began his career in the Bundesliga in 1982 with Borussia Mönchengladbach. From 1989 to 1994, he played for VfB Stuttgart as left wing back.
He returned to Borussia Mönchengladbach for the season 1995-1996 but then had his first stay abroad in the 1996-1997 season with Manchester City.
After playing for South Carolina Freiburg and a last season for Borussia Mönchengladbach, he ended his player career in May 2000. Frontzeck started as assistant coach of Borussia Mönchengladbach from 2000 to 2003 and for Hannover 96 from 2004 to 2005.
He was head coach of Alemannia Aachen from 13 September 2006 until the end of the season 2006-2007 when he resigned due to the club"s relegation. In January 2008, he was named head coach of Arminia Bielefeld and took over for interim head coach Detlev Dammeier after the winter break.
Eventually, it was announced that his contract was extended until 2010 but on 17 May 2009, Frontzeck was fired.
On 3 June 2009, Borussia Mönchengladbach announced Frontzeck"s return to the team as new head coach. He signed a two-year-contract until 30 June 2011. Following the loss against Football Club Saint Pauli on 13 February 2011 Frontzeck was released as head coach by the club management of Borussia Mönchengladbach.
He finished with a record of 16 wins, 14 draws, and 31 losses.
On 3 October 2012, he was named new manager of Football Club Saint Pauli replacing André Schubert. He was sacked on 6 November 2013.
He finished with a record of 15 wins, 10 draws, and 5 losses. He was appointed the new head coach of Hannover 96 on 20 April 2015.
His first match was a 2–1 loss to 1899 Hoffenheim.
To finish out the 2014-2015 season, Hannover defeated Football Club Augsburg and South Carolina Freiburg, both by a 2–1 scoreline, and two draws against VfL Wolfsburg and Werder Bremen. On 28 May 2015, Hannover removed the interim tag and gave Frontzeck a two–year contract. He resigned on 21 December 2015.
He finished with a record of seven wins, four draws, and 13 losses.
As of 29 December 2015.