Glenn Irwin reduced his deficit to British Superbike series leader Tommy Bridewell to just 7.5 points by winning Saturday's sprint race at Oulton Park.
Irwin's victory was an emotional one in light of the recent death of his team's owner Paul Bird at the age of 56.
The PBM Ducati rider won by 0.39 seconds from Lee Jackson, with Leon Haslam third and Bridewell fourth.
Irwin led from the start and will hope for further success in Sunday's two feature races at the Cheshire circuit.
The Northern Ireland rider continued to keep team-mate Bridewell at bay for most of Saturday's 12-lapper, with Jackson also keeping close company with the two pacesetters.
The three were involved in a thrilling battle going into the final lap but Irwin ran slightly wide on the exit of Old Hall, allowing Bridewell to hit the front for the first time.
Irwin regained his position at the head of the field at Island, but Bridewell's hopes of victory were extinguished when he went into Hizzy's too hot and had to run straight on.
For Irwin it was a seventh win of the season.
Davey Todd was 12th in his maiden ride for the NI-based TAS team and Michael Dunlop 19th for Hawk Racing Honda.
In the Superstock 1000cc race, Donegal's Richard Kerr came home second behind winner and series leader Dan Linfoot to keep up his challenge for the championship honours.
Alastair Seeley clinched the final podium place in third, with David Allingham ninth and Simon Reid 14th.