It was an action-packed, drama-ridden three hours of football at the Adelaide Oval last Sunday evening which saw Collingwood lead the Adelaide Crows for a grand total of 21 seconds, and at the final siren.

But one incident late into the mate led to worrying scenes for Magpies defender Nathan Murphy, who was hit high in a marking contest with Crows forward Darcy Fogarty which seemingly should have resulted in a whistle for front-on contact.

Post-match, Magpies coach Craig McRae was questioned about the controversial non-free kick and responded with his surprise at the non-call, with Murphy left to leave the field while bleeding.

"I was astounded by it", McRae told reporters in his post-game press conference.

"One, whether it was a mark or free kick; either you could argue. But then he had blood and he's trying to exit the field, and we didn't get a chance to replace the player in a critical moment.

"I lost my mind."

The call was made more controversial when a free kick was then paid against Magpie Jordan De Goey for deliberate out-of-bounds when it appeared he was trying to clear the ball away from the dazzled Murphy and medical staff.

On the secondary incident, McRae was left fuming.

"He almost hit the doc!... Isn't there a duty of care within that?" McRae added.

The AFL has since admitted to an error in not penalising Fogarty with a free kick against, while also noting a pause in play should have ensued under the blood rule.

"Following a review today of that particular passage of play we acknowledge that the umpires missed the initial free kick and subsequently the process of managing the blood rule was not followed," AFL head of umpiring Dan Richardson said in a statement.

"We have been in contact with Collingwood to clarify the situation."

Fortunately, Murphy escaped without a concussion and McRae revealed no intention of raising a complaint to the league, acknowledging the difficulties that come with officiating an AFL game.

"You could go through every decision they made or didn't make; that's not where we live," he said.

"We make way more mistakes than they do. But you make mistakes and move on that's the way I look at it."

It was the fourth time over the weekend where some seemingly lacklustre officiationg was mentioned by coaches post-match, after Ken Hinkley, Ross Lyon and Chris Fagan all voiced their concerns about separate issues with the umpiring on Friday night and Saturday afternoon when their matches took place.

Coaches have been fined and offered a 'please explain' in the past for criticising umpires in the post-match presser. These instances however, are unlikely to warrant punishment from the league, given the respectful delivery from each.