Indeed, Byrne was now the threat and as both Hickman and Linfoot's tyres began to fade, the former champion pushed his way into third before grabbing second off Rutter heading into the final lap of the race.
Rutter fought back, passing again at Church, only for Byrne to slipstream through again on the run to the final corner Club chicane. However, Rutter coolly pulled off a fine outside move on the tricky corner to get the better of his fellow BSB veteran and snatch second place, his first podium of the year.
Laverty, meanwhile, was already across the line, the Swan Yamaha rider going a long way to make up for his failure to score in either race last time out at Croft. The result also catapults him up to sixth in the standings.
Behind Rutter and Byrne, Hopkins settled for fourth, ahead of Hickman who despite scoring his best-ever BSB finish in fifth, will be aggrieved to have just missed out on the podium. The same can be said for Linfoot, who finished just three seconds off the lead in sixth.
Lowes would end up a distant seventh following a difficult, but promising, wet race initiation on the ZX-10R, the youngster at least getting the better of fellow Kawasaki rider Chris Walker, who took his best finish of the season in eighth.
Josh Brookes and Ryuichi Kiyonari endured quiet races in ninth and tenth, ahead of Steve Brogan on the Jentin Honda and Martin Jessopp on the second of the Rapid Bathams Ducatis.
In the EVO class, Buildbase BMW's Barry Burrell scored the first non-WFR Honda victory of the season, while he also had the honour of finishing ahead of his championship class team-mates in 13th. Glen Richards and Patric Muff rounded out the overall points for second and third in class.
Elsewhere, Hill, Baz and Westmoreland were punished for their risky tyre choices, the trio finishing a lap down on the leaders.
Byrne, meanwhile, will start from the head of the grid for race two after claiming the fastest lap of race one, the HM Plant Honda rider joined on the front row by Rutter, Hopkins and Laverty. Lowes will start in tenth.