Jonathan Rea completed a Misano double and moved to within 16 points of World Superbike leader Alvaro Bautista as he won the final race of the weekend.
The reigning champion from Northern Ireland won Saturday's opener but had to settle for fifth as Bautista took victory in the sprint race.
Bautista slid off while leading the final race and Rea moved to the front with four laps left.
Rea held off a strong challenge from Toprak Razgatlioglu to clinch the win.
It could prove pivotal in the title race as Rea gained 23 points on Bautista, who remounted to finish 14th.
Spanish rider Bautista came off on the second lap to open the door to Rea, who moved behind Razgatlioglu before edging in front.
"The conditions were tough with the tyres moving underneath and I tried to minimize the risk in what was an awesome race," Rea told Eurosport.
"I'm very happy - it was a very important race for me and it's very nice to win it."
Leon Haslam completed the podium and he was followed in by Alex Lowes, Michael Ruben Rinaldi and Tom Sykes.
Earlier on Sunday, Rea recovered from a spill to finish fifth as Bautista eased to a sprint race victory.
Rea led before Bautista moved in front on lap three while Lowes finished second and Haslam third.
|2019 WSB Riders' Championship|
|Alvaro Bautista (Spa)||Ducati||330 pts|
|Jonathan Rea (GB)||Kawasaki||314|
|Michael van der Mark (Ned)||Yamaha||188|
|Alex Lowes (Ned)||Yamaha||164|
|Leon Haslam (GB)||Kawasaki||153|
|Toprak Razgatlioglu (Tur)||Kawasaki||116|