Chaz Davis secured a double in Germany but another second-place finish for reigning World Superbike champion Jonathan Rea saw him extend his lead at the top of the standings.
Race 2 mirrored the result of the first race at the Lausitzring on Saturday.
Davies and Rea were both third-row starters but managed to manoeuvre their way through the field, with Kawasaki rider Rae taking up the lead by lap five.
Davies was soon challenging him, however, and his Ducati hit the front at the midway point before he took command of the race.
Marco Melandri, who started on pole, finished third to complete the podium while Rea's main title challenger, Tom Sykes, was fourth as the gap increased to 70 points with four rounds remaining.