Calgary has won back-to-back games and Detroit has lost two in a row.
Glencross scored the only first-period goal and tallied again 5:47 into the second. Blake Comeau also scored in the second period for the Flames.
Ty Conklin gave up the three goals on 27 shots.
It was the second multi-goal game of the season for Glencross, who has 13 goals for the campaign. Calgary will play its next seven games on the road.
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