After making 11 stops in the opening period, Gillies, was tasked holding off a surging Edmonton squad who put 27 shots on net in the final 40 minutes.
One of his strongest efforts came late in the second period when Tyler Pitlick and Iiro Pakarinen had short-handed two-on-one opportunity. Pakarinen faked a shot before dishing the puck over to Pitlick, who wired a shot on net from close range. Gillies managed to get a shoulder on the puck, deflecting it out of harms way.
"I felt good," Gillies stated. "I'm still getting back into game shape a bit more but it's always nice to see 40 shots. I felt okay."
Pakarinen opened the scoring at 11:08 of the first period, get a stick on a bouncing puck in front of Gillies. Mitchell Moroz put a wrist shot on net from the top of the left face-off circle and the rebound bounced to the right of Gillies. Kyle Platzer backhanded it towards the Flames net and Pakarinen was able to knock it past Gillies.
Under two minutes later, defenceman Kenney Morrison tied the game when he snapped a shot under Cam Talbot's glove. Mark Jankowski, playing in his first NHL pre-season game, carried the puck in the zone and slipped a backhand pass through an Oilers defender to get it to Morrison in the slot. Gillies also picked up an assist on the tally.
"I honestly don't think in the three years we played together at Providence, we combined on a goal together so that was pretty cool," Jankowski said of Gillies' point.
"That assist, it was a great play all around. (Morrison) really jumped up and obviously has a heck of a shot."
Freddie Hamilton gave the Flames a 2-1 lead at the 14:38 mark of the opening stanza when deked around a defender and picked the top left corner, beating Talbot on the blocker side.
The Oilers evened things up early in the third period with a power play tally. Matt Benning took a pass from Adam Larsson and put the puck on net. Forward Ryan Vesce, who was perched at the top of the crease, deflected the shot past Gillies at 3:24.
Pitlick gave the Oilers a lead at 6:00 of the third period when he tucked in a rebound in the crease. Tyler Beck had taken the puck hard to the net, with Gillies making the initial stop, and Pitlick came in to knock it in.
Kris Versteeg added the Oilers fourth goal at 16:37 of the third period, coming in all alone and backhanding a shot over Gillies.
The Flames are back in action on Tuesday night, taking on the Winnipeg Jets at the MTS Centre at 6:00 PM MT.
The next pre-season contest at the Scotiabank Saddledome takes place on Friday when the Flames host the Vancouver Canucks at 7:00 PM MT.
