As a result, with four laps to go, Haslam led Camier, Baz and Sykes, but just a lap later Camier would be off the circuit after crashing at Becketts, a cruel end to a race that had seen the Suzuki rider challenging for the podium throughout, while Haslam had Baz and the charging BMW Italias of Ayrton Badovini and Michel Fabrizio for company now.
However, with the leaders always more tentative than the following pack, the lead would constantly change hands in the final laps with Haslam dropping back, allowing Badovini, Baz, Fabrizio and Jonathan Rea to battle it out.
Heading into the final lap, Fabrizio was the surprise leader, ahead of Rea, Baz and Badovini, an order they maintained heading onto the Hangar Straight for the final time.
At this stage, Rea looked the most confident, but the long straight would allow third place Baz to slipstream the two riders ahead of him and scythe past both Rea and Fabrizio into the lead at Stowe.
With just two corners remaining, rookie rider Baz held his nerve – despite wobbling on the wet kerb across the finish line – to complete one of World Superbikes' most surprising victories.
A second win of the season for Kawasaki, Baz's result was arguably the most deserving beyond his bravery in the closing stages since he had been battling towards the front in the dry from the very beginning regardless.
Drama continued to unfold behind the leaders, however, with Fabrizio just holding off Rea through the long final bend, in turn opening a gap for team-mate Badovini to slip through. However, Badovini's momentum carried him onto the slippery kerb, sending him spectacularly off the bike.
Remarkably, he was still classified in third, despite being on the floor as he came across the line, while Rea was fourth despite ploughing into the BMW having had nowhere to go.
Though title contenders Max Biaggi and Marco Melandri didn't make too much of an impression at the front, the race could prove a pivotal moment in the championship fight after Biaggi crashed heavily on the final lap when he touched the kerb. Though Melandri couldn't capitalise entirely as he scored nine points for seventh, it does reduce Biaggi's lead to 14 points now.
Elsewhere, Checa and Haslam were left a rather disgruntled fifth and sixth having led most of the way between them, while Sykes favoured caution on the way to eighth after falling back when the rain began.