Jonathan Rea secured his fourth double victory of the season in Portimao to extend his overall World Superbike Championship advantage.

Kawasaki rider Rea moved 124 points clear of Tom Sykes as he made it 10 wins in 14 races so far this season, in doing so making it 15 podium finishes on the trot and passing Carl Fogarty for the third longest streak in series history.

The opening race was blighted by rain with Rea and Sykes playing a game of cat and mouse on the front before the weather worsened after 14 laps and forced the riders in to change tyres.

Rea made his decision to pit a lap before Sykes, and a mistake from his Kawasaki team-mate meant a winning gap of more than nine seconds by the time the chequered flag came out.

Sykes held on for second ahead of Chaz Davies, who came out on top of Leon Haslam in an early dice, but Haslam's race was ruined by a later fall and he could only trail home in 12th.

The sun had come out by the time race two started but Rea had few problems in re-establishing his dominance after Sykes set the early pace, eventually coming home more than five seconds clear.

Ducati's Davide Giugliano and Sykes had a dice for second place, but it was the Frenchman who came out on top after Sykes suffered an apparent technical issue and dropped all the way back to eighth.

That left Haslam to make up for his first race bad luck by finishing third - his first podium since round three in Aragon in April.

Race One result:

1 J Rea (Gbr) Kawasaki 37 mins 10.092 secs

2 T Sykes (Gbr) Kawasaki +9.384secs

3 C Davies (Gbr) Ducati +13.753

4 D Giugliano (Ita) Ducati +27.818

5 S Guintoli (Fra) Honda +28.141

6 M Baiocco (Ita) Ducati +39.665

Race Two result:

1 J Rea (Gbr) Kawasaki 34 mins 33.783 secs

2 D Giugliano (Ita) Ducati +5.416secs

3 L Haslam (Gbr) Aprilia +6.689

4 C Davies (Gbr) Ducati +10.445

5 M van der Mark (Ned) Honda +14.122

6 S Guintoli (Fra) Honda +14.265

Championship standings:

1 J Rea (Gbr) Kawasaki 330 points

2 T Sykes (Gbr) Kawasaki 206

3 L Haslam (Gbr) Aprilia 199

4 C Davies (Gbr) Ducati 184

5 J Torres (Esp) Aprilia 131

6 S Guintoli (Fra) Honda 113