Ulster Senior Lcague champions ran out winners against Derry City by the odd goal in five.
Cockhill Celtic 3-2 Derry City Reserves
After an even opening, Cockhill hit the front when Finn McClure's cross was headed home at the back post by Garbhan Friel.
Cockhill were on top and could have added a second when Caolan McColgan hit the bar after an advantage was played on the right hand side.
McColgan had another chance when pressure from Friel forced an error in the Derry defence but he hesitated and Jack Lemoignan saved.
Patrick Ferry looked dangerous for Derry and dragged a shot wide before having a snapshot narrowly over after he reacted first to a free kick.
Derry equalised when a ball into the left channel released Ferry whose low cross was converted by Mark Mbuli.
Cockhill responded with a Corey McBride run but he was indecisive and the chance was gone.
The last chance of the half fell to Derry when they worked the ball to the edge of the box where Jack Malone's shot was tipped over by Daniel Houghton.
The second half started scrappily, the first chance coming on 59 minutes when a quick corner from Cockhill found Garbhan Friel but he scuffed the shot.
Cockhill re-took the lead on 62 minutes when Laurence Toland, having only come on as substitute, produced a sumptuous first time finish to the far corner from the inside left position after good work from Jason Breslin and Caolan McColgan.
Derry were still well in the match with Mbuli going close with a shot that Houghton saved at his near post.
Derry equalised for a second time on 73 minutes when Orrin McLaughlin struck a free kick over the wall from the edge of the box.
Parity was short lived when Cockhill struck for the winning goal on 77 minutes, Caolan McColgan made ground down the right crossing to Friel whose effort but the bar but Corey McBride was on hand to force the ball home from close range.
Cockhill saw the game out after this to get their title defence off to a winning start.
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