Derek Sheils dominated at the Cookstown 100 to clinch a double in the Open and feature Superbike races.

Sheils, who won the Superbike race at the Tandragee 100, beat Derek McGee in the first Open race by 2.5 seconds, with William Dunlop a close third on the Temple GC Yamaha R1M.

Guy Martin finished fifth on the Honda Racing Superstock machine as he returned to the Orritor event for the first time since 2015.

Sheils was an even more commanding winner of the feature race on the Cookstown B.E. Racing Suzuki as he headed McGee by 11 seconds at the finish, with Sweeney squeezing out William Dunlop for the final place on the rostrum.

Martin did not start the race on his Honda, although he did compete in the Supersport race on a CBR600RR in the Wilson Craig colours, finishing eighth.

The race was won by Adam McLean on the MSS Kawasaki from McGee and James Cowton, who was riding the McAdoo Kawasaki.

Yorkshireman Cowton won the Supertwins race for the Cookstown-based team after getting the better of McGee on the final lap.

Cookstown is the last Irish road race before the North West 200 kick-starts the international meetings in May.