It was midway through the third period of that game when Smith was playing the puck behind Edmonton's net, and Lucic barreled in to send them both flying against the end boards.
Lucic was assessed a five-minute major for charging and a game misconduct for the incident. Smith was forced by NHL concussion spotters to briefly leave the game and be assessed. It was 4-0 Edmonton at the time in a series that was tied 1-1.
Oilers backup Mikko Koskinen stepped in for 4:19 and didn't face a shot before Smith returned to close out a 4-1 Edmonton victory.
When Lucic addressed what happened for the first time on Monday, he denied any malicious intent towards Smith.
"I definitely wasn't trying to hit him," Lucic said. "I was braking. ... If I actually did charge, we both wouldn't be playing [in Game 4]."
That was in line with what Flames coach Darryl Sutter said after Game 3 in response to Lucic's ejection.
"They called it charging, correct?" he said. "Could you imagine if [Lucic] did charge? What would happen there? He actually tried to slow down a bit, I think. It is what it is. It's the score [being 4-0] and who it was."
Lucic will not face any supplemental discipline from the NHL for what happened, and he declined to comment further on the incident.
"I don't think I really want to get into what I was thinking," he said, "or what I was trying to do or if [Smith] sold it or if he didn't, a little bit."
In the moment, Smith said he wasn't sure what to make of the hit.
"I don't really know what happened," Smith said. "I was out playing the puck and all of a sudden I'm getting buried into the boards. When you're getting run through the end wall and not expecting it, it's not an ideal situation."
The hit itself was one thing. The bigger issue for Smith was being made to leave the game when he didn't feel it was necessary. Smith acknowledged his helmet flew off but said his head didn't hit anything.
"It's not an ideal situation to [exit] in the third period with 11 minutes left, but I get the reason for it," he said. "I think the player should have some say in that, but obviously it is what it is."
Smith will be Edmonton's projected starter again when it hosts Calgary in Game 4 on Tuesday.