Max Biaggi has more than doubled his World Superbike Championship lead after cruising to his seventh win of the season at Misano while Leon Haslam limped home in eighth.

The Aprilia rider held station behind long-time leader Troy Corser for two-thirds of the race before pouncing into a lead he wouldn't lose with nine laps remaining.

Crucially, with Haslam only managing a distant eighth after failing to recover from a poor start, Biaggi's maximum points' haul has seen him extend his advantage to 32 points in the overall standings.

Having given BMW its first pole position during qualifying, Corser turned his grid advantage into an early lead, followed by Biaggi, Checa, Sylvain Guintoli and Michel Fabrizio.

Haslam, meanwhile, suffered a poor opening lap, getting shuffled down to ninth after being run out wide by Guintoli through the first bend, the erstwhile series leader caught behind Jonathan Rea, who had turned his 16th place starting position into an early eighth.

Haslam would promptly relieve Rea of the position on lap three, but with Cal Crutchlow and Noriyuki Haga all tripping over one another in the battle for sixth, the top five made a swift break.

The gap between the two groups was widened further when Crutchlow, having passed Haga for sixth, low-sided into retirement on lap four.

The leading group would slim to three as Corser attempted to make a break mid-race, the Australian being chased by Biaggi and Checa, while Fabrizio and Guintoli began to fade.

The battle for the win, however, would come down to a ten-lap sprint, sparked when Biaggi swept past Corser on lap nine. Although Corser got his rival back almost straight away, another shuffle would see Biaggi emerge out front.

Corser pushed on, eager to respond to Biaggi, but would only be successful in running too deep at the Quercia left-hander and allowing Checa to sneak past.

Assuming the mantle for chaser, Checa immediately began to apply pressure to Biaggi, but the experienced Italian would not be denied, the 39-year-old crossing the line to record his seventh win - his third on home soil this year.

Checa's second went some way to making up for his Miller double DNF disaster, while Corser was left a rather frustrated third, the BMW rider disappointed not to win but happy with what remains only the team's second WSBK podium.

Fabrizio came home a quiet fourth at Ducati's home track, while Guintoli put in his best result since the Phillip Island opener in fifth.

His Suzuki team-mate Haslam, however, didn't fare so well, the Briton getting as high as sixth before being overtaken by a charging Leon Camier - up from 14th on the grid - mid-race, while Haga would go on to re-pass on the very final lap.

Shane Byrne and James Toseland were others to make some gains on their lowly grid spots in ninth and tenth, ahead of Luca Scassa - who worked his way up to 11th having dipped as low as 17th at one stage - and Lorenzo Lanzi.

Rea's weekend continued to go from bad to worse, the Ulsterman's early rally the only highlight as he steadily slipped down the order to an eventual 13th. His team-mate Max Neukirchner followed him in 14th, while Tom Sykes rounded out the points' paying positions in 15th.