That means it is advantage Edinburgh ahead of the second leg at Scotstoun Stadium on Saturday January 2 live on Sky Sports.
But Edinburgh will know how dangerous it is to celebrate too early after they came back from a ten-point deficit after the first leg of last year's 1872 Cup to lift the trophy.
And Coman is determined to not let that happen to his side this time around.
"It was a brave performance," Coman told The Scotsman. "A great effort, especially in that last ten minutes. It showed a lot of character.
"Some of the experienced guys were off and younger subs were on and they held it together well - just.
"But it is a job half done, of course. We came away with a loss in the first game last year and ended up winning the thing.
"We've got to be focused and I said in the huddle it's only half done and we need to get the fire in the belly and head to Scotstoun now.
"We'll have to wait and see if 12 points is enough but it's a good start."
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