Rea had won the first race of the weekend on Saturday and followed it up on Sunday to further stamp his dominance on the season.
Josh Brookes got off to a fine start but Rea grabbed the lead as an intially wet race dried out quickly.
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Rea claims victory in World Superbike opener in Assen
16/04/2016 AT 12:05
Both Rea and Kawasaki team-mate Tom Sykes came into the pits quickly for a tyre change, allowing them to steal a march on the field.
The duo then pulled clear of the field, with Rea winning and Sykes finishing second. Michael van der Mark was third.

Rea completes second win of weekend in Assen

Race results

1. Jonathan Rea GBR Kawasaki Racing ZX-10R 21 lap
2. Tom Sykes GBR Kawasaki Racing ZX-10R +2.442
3. Michael van der Mark NED Honda Racing CBR1000RR +15.189
4. Lorenzo Savadori ITA IodaRacing Aprilia RSV4 +25.507
5. Chaz Davies GBR Racing Ducati 1199R +30.853
6. Nicky Hayden USA Honda Racing CBR1000RR +36.458
7. Alex Lowes GBR PATA Crescent Yamaha R1 +39.263
8. Davide Giugliano ITA Racing Ducati 1199R +46.789
9. Leon Camier GBR MV Agusta RC F4 RR +65.023
10. Xavi Fores ESP Barni Ducati 1199R +65.468
11. Sylvain Guintoli FRA PATA Crescent Yamaha R1 +84.948
12. Roman Ramos ESP GO Eleven Kawasaki ZX-10R +95.035
13. Lucas Mahias FRA Pedercini Kawasaki ZX-10R +1 lap
14. Karel Abraham CZE Milwaukee BMW S1000RR +1 lap
15. Jordi Torres ESP Althea BMW S1000RR +1 lap
16. Markus Reiterberger GER Althea BMW S1000RR +1 lap
17. Matthieu Lussiana FRA Team ASPI BMW S1000RR +1 lap
18. Pawel Szkopek POL Team Toth Yamaha R1 +1 lap
19. Peter Sebesteyen HUN Team Toth Yamaha R1 +2 lap
20. Dominic Schmitter SUI Grillini Kawasaki ZX-10R +2 lap
Rea completes second win of weekend in Assen
17/04/2016 AT 12:48
Rea back on song with Assen win
16/04/2016 AT 17:28