Second-seeded Stanislas Wawrinka was upset by German wild card Dustin Brown 6-7 (6), 6-4, 7-5 in the first round of the BMW Open on Tuesday.
Wawrinka, making his debut in Munich, was the only seed not to win his opener.
Born in Germany to a Jamaican father and a German mother, Brown lived in Jamaica and was ranked No. 123, 109 spots below Wawrinka.
Brown wasted an opportunity to serve out the match at 5-4 but broke Wawrinka's serve a fourth time to close it out.
Also through were third-seeded Marin Cilic of Croatia, No. 5 Florian Mayer of Germany, No. 7 Nikolay Davydenko and No. 8 Philip Kohlschreiber of Germany.
Cilic hit 11 aces past Simone Bolelli to beat the Italian 7-5, 7-6 (4). Theirs was a match of former finalists, Cilic last year and Bolelli in 2008.
Davydenko, one of three past champions in the field, beat fellow Russian Andrey Kuznetsov 6-1, 7-6 (4), and Kohlschreiber, the last local winner in 2007, routed Colombian qualifier Robert Farah 6-3, 6-1.
Mayer, Germany's highest-ranked player, won for the first time in four attempts in Munich with a 6-1, 6-2 defeat of Belgian qualifier Steve Darcis.
In all, six Germans reached the second round, including Philipp Petzschner, Denis Gremelmayr and Julian Reister.
Also, former No. 2 Tommy Haas returned to competitive tennis after an injury break of 14 months and lost his doubles with Radek Stepanek of the Czech Republic to Simon Aspelin and Paul Hanley 2-6, 6-3, 10-8.
Other first-round singles winners were Stepanek, Teymuraz Gabashvili of Russia, and Potito Starace of Italy.