Jonathan Rea saw his World Superbikes Championship lead cut to 26 points in Germany after crashing in a race won by Welshman Chaz Davies.
Reigning champion Rea was unscathed in the crash on lap six with his main title challenger and Kawasaki team-mate Tom Sykes finishing second.
American Nicky Hayden completed the podium in Saturday's opening race, dominated by Ducati rider Davies.
Davies led from start to finish to win by more than 10 seconds.
The championship resumed at the Lausitzring circuit following a two-month break.
Rea failed to finish for the second successive race, seeing his series lead shrink by 45 points as Yorkshireman Sykes picked up a win and second place.
Davies, who enjoyed a sixth win this season, consolidated third place in the standings but he trails Rea by 83 points and is unlikely to be a title threat.
Following the second race on Sunday, the riders have three rounds remaining in France, Spain and Qatar.
|World Superbike Championship 2016|
|1. Jonathan Rea (GB)||Kawasaki||368|
|2. Tom Sykes (GB)||Kawasaki||342|
|3. Chaz Davies (GB)||Ducati||285|
|4. Michael van Der Mark (Ned)||Honda||195|
|5. Davide Giugliano (Ita)||Honda||194|
|6. Nicky Hayden (USA)||Honda||189|