Calgary lost 7-2 in Edmonton Wednesday night in their penultimate preseason outing.
They are now 4-2-1 in exhibition play.
Nikita Zadorov and Walker Duehr scored for the Flames who iced a young lineup, while Dan Vladar made 35 saves.
The Flames 2023 first-round pick Samuel Honzek left the game in the first period and didn't return. Head coach Ryan Huska said after the game he is day-to-day.
The veteran-laden Oilers side built a quick 2-0 lead off a powerplay marker by Connor McDavid at 5:55, followed by the Oilers captain feeding Connor Brown who tallied at 7:27.
Zadorov would cut into the lead at 15:44 when he finished off an end-to-end rush with a seeing-eye wrister that beat Stuart Skinner low shortside under his glove.