Born in
Bobingen,
Bavaria, Holzer graduated from karting in 2003, and raced at the
Formula BMW ADAC formula championship from 2004 to 2006. In 2006, he competed at the
Formula 3 Euro Series, where he scored no points. In 2008, Holzer switched to sports car racing, finishing fifth at the
Porsche Carrera Cup Germany. He signed as Porsche junior works driver, and raced at the 2009
FIA GT Championship for
Prospeed and
VLN for
Manthey, in both cases driving a
Porsche 911. Holzer became a Porsche works driver in 2010. That year, he resulted vice-champion at the
FIA GT3 European Championship for Prospeed with two wins. Also, he raced in several endurance races, such as the VLN for
Manthey, the
Le Mans Series for
Prospeed,
Petit Le Mans for
Flying Lizard, and the
24 Hours of Le Mans for
BMS Scuderia Italia, resulting third in the GT2 class. Holzer competed partial-time at the 2011
American Le Mans Series for
Flying Lizard, the five rounds of the
Le Mans Series for
Prospeed, and the VLN, where he got an overall win with a hybrid Porsche 911. In 2012, Holzer raced full-time at the American Le Mans Series for
Flying Lizard in the GT class, collecting a best result of fifth at Virginia, and the
International GT Open for
Manthey, winning three races and resulting vice-champion in the Super GT class. The driver switched to
Paul Miller Racing for the
2013 American Le Mans Series, still as Porsche works driver, resulting 13th in the GT class. Holzer was dropped by Porsche in late 2014. In 2016, Holzer joined
Abt Sportsline to compete at the
ADAC GT Masters with a
Bentley Continental GT. ==Racing record==