The incident took place eight minutes into the third period of Wednesday's game between the Sharks and Avalanche. Blichfeld connected on a hit on an unsuspecting MacKinnon as the latter was turning, with his shoulder clipping MacKinnon's head.
The Avalanche pivot stayed down for some time, kneeling over and appearing to try and collect himself, while a scrum ensured around Blichfeld.
The Sharks winger was handed a match penalty, after which Colorado captain Gabriel Landeskog tallied his club's third goal of the night on the power play, part of an eventual 4-0 win.
"I think our team responded well to it," said Avalanche defender Devon Toews in a post-game interview with Altitude TV. "I don't think we liked the hit very much. And guys stepping in to protect a teammate is what we want. You know, we need that [aggression] from our team, in order to step in when things like that happen. Our response to it, I think, was pretty good."
After the game, Avalanche head coach Jared Bednar suggested his club might've avoided a worst-case scenario.
"He seems to be doing good. I think we get lucky on it," he said, according to The Athletic's Peter Baugh. "...As of right now he seems to be fine."
It is not known at this time if MacKinnon will miss time as a result of the hit.
The Avalanche play next on Friday, taking on the Anaheim Ducks to kick off a nine-game home stand that'll see them also face Arizona, Los Angeles and Minnesota.