Dubliner Derek Sheils continued his impressive early-season form by taking a hat-trick of wins at the first round of the Adelaide Mondello Park Masters.
Kawasaki-mounted Sheils won race one and race three from Waterford's Brian McCormack, with Gerard Kinghan from County Antrim third in both events.
Kinghan was runner-up in race two after McCormack overshot at the first corner.
Robert English enjoyed a treble of wins in the Supersport 600cc races, with Conor Parkhill second on two occasions.
Richie Ryan was second in the final Supersport outing of the weekend with 20-year-old Ahoghill rider Luke Johnston taking third spot.
Bike Bits NI Kawasaki rider Sheils was also victorious at the Irish Short Circuit Championship meetings over the Easter weekend, winning the Enkalon Trophy at Bishopscourt and the feature Mayor's Trophy race at Kirkistown.