Nurnberg, Germany (SportsNetwork.com) - Top seed Andrea Petkovic came up an opening-round loser Monday at the Nurnberg Cup tennis event, a final clay- court French Open tune-up.

Russian qualifier Yulia Putintseva was leading Petkovic 5-0 in the first set when the German retired with an apparent leg injury on the red clay at Tennis- Club 1.FC Nurnberg.

Petkovic was the 2013 Nurnberg runner-up to Simona Halep.

Two other top seeds avoided upsets, as No. 2 Angelique Kerber of Germany topped Swedish qualifier Rebecca Peterson 7-5, 6-4 and No. 3 Sabine Lisicki of Germany took care of Spaniard Silvia Soler-Espinosa 6-4, 7-5.

In other action involving seeds, Japanese qualifier Misaki Doi mauled No. 5 Anna Karolina Schmiedlova of Slovakia 6-2, 6-1 and No. 8 Carina Witthoeft of Germany got past Belgian qualifier Alison Van Uytvanck 6-7 (2-7), 6-3, 6-3.

Several other women reached the second round, including Swiss Stefanie Voegele, Czech Klara Koukalova and German wild card Anna-Lena Friedsam.

On Tuesday, a second-round affair will pit Kerber against Koukalova.