Allan Delferriere, Robbie Hamilton, and Josh O’Connor found the net in the opening period while a Dylan Tait penalty and strikes by substitutes Rudi Molotnikov and Jacob MacIntyre ensured a big win for the visitors, with Jonny Edmond on target for the hosts.
Gareth Evans and Steve Kean fielded a strong starting line-up at New Countess Park with Under-18s defender Owen Hastie filling the left-back slot in the absence of Oscar MacIntyre, who is expected to be involved again with the first team at the weekend.
Hibs started strongly with Delferriere sending a powerful effort just wide of the post and Dunbar goalkeeper Sean Brennan, a former Hibs youngster, denied Joao Balde and Robbie Hamilton with two smart saves.
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Delferriere eventually opened the scoring after 15 minutes but the ‘keeper kept the hosts in the match with a penalty save from O’Connor, awarded for a push on Hamilton.
Hamilton and O’Connor combined for Hibs’ second, Tait’s long ball up the line being collected by the striker who hit the byline and cut it back for the arriving Hamilton to slot home from close range.
O’Connor made it three shortly before the interval, turning in Murray Aiken’s pass into the bottom corner.
Hibs kept up the pressure in the second period but Kevin Haynes’ side put up a stronger resistance. Shortly before the hour mark Hibs were awarded a second somewhat soft penalty for a foul on Hamilton.
Tait stepped up and sent Brennan the wrong way with a powerful effort into the bottom corner.
Dunbar pulled a goal back when Edmond headed home at the back post but Molotnikov, on for the impressive Tait, scored Hibs’ fifth when he netted from close in following good work by Balde and O’Connor.
Two substitutes combined for the sixth, Harry Wright’s cutback picking out Jacob MacIntyre who swept the ball into the far corner.
The final score might have been greater but Brennan, rightly picked out as man of the match, made a number of fine saves to frustrate Hibs in both halves.
The Hibs development side are next in action against Chesterfield on Monday August 1 and Newcastle on Saturday August 6, both at HTC.