Richard Cooper stamped his authority on the Pirelli National Superstock 1000 class this afternoon with a clean sweep in today's two-part race as he stretched his lead in the title chase.

The Buildbase Suzuki man dropped down to fourth before battling back to the front as he fended off Chrissy Rouse and Alex Olsen to secure his third win of the year.

Cooper got the best start in the first 22-lap dash, hitting the front ahead of title challenger Mackenzie and Scotsman Lewis Rollo, but a moment for the EHA Aprilia rider on the very first lap allowed Morello Racing's Chrissy Rouse to slot into third.

But hot on the Geordie's heels was Alex Olsen, who moved up to third moments later as Levi Day joined the breakaway front five.

As Mackenzie dropped into the clutches of Team IMR's Olsen, Rouse followed Olsen through to go third and stretch a slight gap over Mackenzie and Day in fourth and fifth.

Back at the front, Rouse set his sights on Cooper after sticking a pass on Olsen at Roberts on lap 10, but former champ Cooper wasn't having it and powered to a nearly one-second lead.

Backmarkers came into play and allowed Rouse to close the gap back down to just half a second with five laps remaining, but Cooper regained a two-second advantage as Olsen moved back into third.

And despite a move at Redgate on the final lap, Olsen got back ahead to nick third from Rouse as Cooper took victory almost 2.5s up the road.

After the 10-minute pit stop, Cooper again got a strong start, but it was Team WD-40's Eemeli Lahti who shot forward from fourth to second ahead of Rouse before Mackenzie passed Rouse at the bottom of Craner to tuck into third.

But the Finn wasn't done with second and he lunged up the inside of Cooper at Starkey's on lap two to hit the lead as Mackenzie followed him through before Cooper fell to fourth behind Rouse.

Cooper then had a go at Lahti just before the Old Hairpin and continued his charge to stick a pass on Mackenzie at Mclean's, hitting the front for the start of lap four.

But Mackenzie was straight back in front at Redgate before Rouse passed him back almost a full lap later at Roberts as the two continued their tit-for-tat.

The Bathams Racing rider lost ground after a few laps, however, as Cooper regained his momentum and passed Lahti before stealing the lead from Rouse at Redgate on lap eight.

From there, the 2011 champ was never bothered as he powered to a lead of WWWs, while Rouse held off the advances of Olsen to clinch his first podium of the season in second.

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