Fourth-seeded Florian Mayer of Germany advanced to the quarterfinals of the Moselle Open, beating James Blake 6-7 (4), 6-3, 6-4 on Wednesday.
Mayer broke the American in the ninth game of the deciding set and served out for the victory. He will next meet fifth-seeded Andreas Seppi of Italy or Frenchman Vincent Millot.
Seppi reached the second round with a 6-7 (7), 6-3, 6-4 win over Croatia's Ivan Dodig in a scrappy match which saw 14 breaks of serve overall.
Later, top seed and defending champion Jo-Wilfried Tsonga of France plays countryman Clement Reix in the second round.
In remaining first-round matches, American Jesse Levine beat Cedrik-Marcel Stebe of Germany 6-3, 6-2, and Michael Berrer of Germany advanced when Jan Hajek of the Czech Republic retired while trailing 6-4, 2-0.