Poleman Davies held the lead on the run into the Andretti Hairpin at the start of the 25-lap race, with Rea nipping ahead of Kawasaki teammate Tom Sykes for second.

Rea attempted to take the lead at the final corner, but ran in too hot and Davies used his superior drive from the turn to reclaim the position as they started lap two.

Davies and Rea ran astern for the next five laps, easing two seconds clear of Sykes, who had Yamaha's Alex Lowes and the Milwaukee Aprilia of Eugene Laverty reeling him in.

A mistake for Davies at the Corkscrew allowed Rea to scythe up the inside and relieve the Ducati rider of the lead on lap seven, and the Ulsterman proceeded to keep Davies within seven tenths of a second up until the final few tours.

Davies managed to get to within six tenths of Rea with five laps to go, but a mistake put his deficit up to close to two seconds, which gave Rea a comfortable run to the chequered flag for his seventh win of the season.

Lowes crossed the line a distant third for his third rostrum appearance of the year on the Yamaha, with Laverty two seconds down in fourth. He will start race two from pole.

Marco Melandri recovered from a lowly 10th on the grid to snatch fifth away from Ducati stablemate Xavi Fores on the Barni bike in the closing stages, while Sykes slid to seventh at the end.

Michael van der Mark (Yamaha) put Sykes' seventh under pressure in the closing stages, but was just half a second shy at the line.

Jordi Torres got his MV Agusta home in ninth, while Jake Gagne ended his home race 10th on the sole remaining Honda, after teammate Leon Camier retired with seven laps to go and Triple M Racing's PJ Jacobsen was punted off at the Andretti Hairpin by Leandro Mercado (Orelac Kawasaki).

Mercado crashed at the Corkscrew just moments after the Jacobsen collision, while Toprak Razgatlioglu (Puccetti Kawasaki) suffered a nasty highside at the same corner with six laps to go, and was taken to the medical centre for checks.

Lorenzo Savadori fell from his Aprilia at the final corner on Lap 1, then remounted and benefitted from the attrition around him to finish 14th ahead of fellow crasher Loris Baz (Althea BMW).

Wildcard Josh Herrin was running inside the points when his Attack Performance Yamaha developed an issue with six laps to go. Fellow WSBK rookie Karel Hanika scored points on his debut in 13th for Guandalini Yamaha.

Rea's victory means he further extends his championship lead to by five points to 70 over Davies, while van der Mark holds onto third, albeit 91 points adrift.

Race results:

Pos.	#	Rider	Bike	Laps	Gap
1	1	Jonathan Rea	Kawasaki	25	35'15.071
2	7	Chaz Davies	Ducati	25	2.978
3	22	Alex Lowes	Yamaha	25	12.212
4	50	Eugene Laverty	Aprilia	25	14.309
5	33	Marco Melandri	Ducati	25	16.712
6	12	Xavi Fores	Ducati	25	18.929
7	66	Tom Sykes	Kawasaki	25	25.638
8	60	Michael van der Mark	Yamaha	25	26.211
9	81	Jordi Torres	MV Agusta	25	31.579
10	45	Jake Gagne	Honda	25	38.084
11	68	Yonny Hernandez	Kawasaki	25	44.971
12	40	Roman Ramos	Kawasaki	25	45.412
13	98	Karel Hanika	Yamaha	25	50.768
14	32	Lorenzo Savadori	Aprilia	25	1'06.063
15	76	Loris Baz	BMW	24	1 lap
Ret	54	Toprak Razgatlioglu	Kawasaki	19	6 laps
Ret	57	Josh Herrin	Yamaha	18	7 laps
Ret	2	Leon Camier	Honda	17	8 laps
Ret	36	Leandro Mercado	Kawasaki	10	15 laps
Ret	99	PJ Jacobsen	Honda	10	15 laps