Radek Stepanek of the Czech Republic beat seventh-seeded Mikhail Youzhny of Russia 6-4 5-7 6-4 on Tuesday to advance to the second round of the BMW Open.
Youzhny was the second former winner of the clay-court event to be eliminated after two-time champion Nikolay Davydenko lost on Monday. Youzhny was the 2010 winner.
In other action on Tuesday, Australian qualifier John Millman was beaten 6-2 6-2 by Grega Zemlja of Slovenia.
Fifth-seeded Alexandr Dolgopolov defeated Ukrainian countryman Sergiy Stakhovsky 6-4 6-2, while sixth-seeded Florian Mayer of Germany, the 2011 runner-up, struggled to overcome qualifier Lukasz Kubot of Poland 7-6 (7-2) 4-6 7-5.
Wild-card entry Gael Monfils of France topped eighth-seeded Jurgen Melzer of Austria 6-3 6-3, while Evgeny Korolev of Kazakhstan upset Marcos Baghdatis of Cyprus 7-5 7-6 (7-3) and Ernests Gulbis of Latvia beat Jarkko Nieminen of Finland 6-4 6-2.
Viktor Troicki of Serbia defeated German qualifier Matthias Bachinger 6-3 6-2.