Usually busy battling each other on the ice, the Alberta rivals held a rare ceasefire.
The result was an historic peace treaty -- the first trade ever completed between the two franchises.
It took a month of talking with the neighbours to the north to complete the deal, and a heap of Darryl Sutter man-love for defenceman Steve Staios, who was sent down the QE2 from Edmonton to Calgary for blueliner Aaron Johnson and the Flames' choice of their third-round draft pick in either 2010 or 2011.
"I think, at first, when I heard the news, I was mostly excited. Then for a second you realize where you're going, and there's a real healthy rivalry between the two clubs," Staios said after finding out he'd become the answer to a future trivia question.
"The fact that I'm the first one, I think it's something to talk about. But for me, personally, it's not a big deal. I'm a Flame now, and I'll have no problem doing what I do once I get the jersey on.
"I couldn't say this when I was with the Oilers, but I have a high respect level for the team, for the Calgary Flames. There's a lot of high character guys, and everybody plays with a little bit of an edge and with a little bit of grit. I'll tell you, you knew you were in a game when we played against them. That's probably the biggest compliment you could have. I hope the guys feel that way when they play against me."
With one more year on his current contract, which carries a $2.7-million cap hit for next season, Staios could join a short list of players who have suited up for at least 100 games for both Alberta clubs.
Only a handful (see list at right) of the 32 to play at least one game for both sides had extended time with each.
At 36, the rugged rearguard will have to stay healthy to be added to that group.
He won't change his aggressive style to do it, and he won't apologize to any of his new teammates he might have offended in the past, either.
"I think it will be awkward for a couple of minutes," he joked while talking to Edmonton reporters.
"We're all professionals. That's the type of game that I play," he said to the Calgary media. "I have no problem going into that locker-room and interacting and being a teammate with any of the players I've battled with or had tough games against in the past. It's part of the business."