Derek Sheils and William Dunlop produced a clean sweep of the feature races at the Cookstown 100 road races on Saturday, with doubles apiece in the Superbike and Supersport classes respectively.
Dublin rider Sheils won the main Superbike race on the Cookstown B.E. Racing-backed Suzuki by 10 seconds from exciting team-mate Malachi Mitchell-Thomas, who was making his debut at the 2.1-mile Orritor course on the Superstock Suzuki.
Derek McGee had been safe in second place on his BMW but ran wide in the closing stages, allowing Mitchell-Thomas and Mar-Train Racing's Dan Kneen through to fill the podium places.
McGee finished fourth in the end ahead of Dunlop, who was riding the MSS Kawasaki Superstock machine.
Sheils opened his account earlier in the day with victory in the first Superbike race by five seconds from McGee, with Mitchell-Thomas on the rostrum in third. Kneen, Brian McCormack and Dunlop were the top six.
In the Supersport class, Dunlop was unbeatable on the CD-IC Racing Yamaha as he powered through the field to hit the front in the opening 600cc race from McGee and Mitchell-Thomas.
The race was stopped when Mitchell-Thomas came off his Honda unhurt, with Dunlop taking the win from Kneen and McGee.
Dunlop again proved too strong in the second Supersport race at the narrow Co Tyrone course and once he seized the lead from McGee, he pulled away to win by almost three seconds to complete his brace.
Kneen finished third on the Mar-Train Yamaha behind McGee, with James Cowton, Paul Jordan and Czech rider Michal Dokoupil completing the top six.
The Irish National meeting is the final race on the calendar ahead of the North West 200, which takes place from May 10-14.