His one-match ban for what the league deemed a 'minor' breach was ruled to have been served in the Bombers' round-four loss to Carlton, which McKenna missed while he was in quarantine.

The Irish defender visited his former host family on the afternoon of June 19, after a COVID-19 test that morning, and did so without gaining approval for the visit.

The test was confirmed as positive the following morning and led to Essendon's match against Melbourne being postponed indefinitely.

McKenna was immediately sent into quarantine and has since returned three negative COVID-19 results.

Teammate James Stewart was also forced to quarantine after being deemed a "close contact" of McKenna.

The AFL has not yet determined the cause of McKenna's positive test.

The league also investigated McKenna's attendance at rental inspections but will not penalise him over that matter.

Essendon said that had McKenna sought approval for the host family visit, he would have been cleared.

The club accepted the AFL's decision to suspend McKenna.

"This is a minor breach, but a reminder no less to all players of the importance in adhering to the strict protocols the AFL have put in place to ensure the health and safety of those involved in our game, as well as the community," Bombers football manager Dan Richardson said.

"The visit to his former host family is in no way related to returning a positive result to the COVID-19 test given the visit was after his testing was completed on the Friday (June 19).

"We accept that Conor should have first checked with our club's compliance officer prior to visiting the family.

"The club will continue to fully support both Conor and James Stewart, who remains in quarantine, during what has been a challenging period."

McKenna was initially picked to play against Melbourne and while he could now return in the Collingwood clash Zach Merrett will miss out.

The midfielder on Monday accepted a one-match ban for the punch that landed Carlton's Jack Silvagni in hospital.

Silvagni suffered a fractured rib and bruised lung in the incident, which occurred during the Blues' one-point win over Essendon at the MCG on Saturday night.

Merrett's action was graded by the match review officer as careless conduct with high impact to the body.

It sparked furious debate over what many, including Silvagni, deemed a fairly innocuous football incident.

"Shame to see Zach get a week," Silvagni tweeted on Monday.

"Incidents like that happen 20-30 times a game.

"He hit a sweet spot and (the) outcome is just unlucky, no malicious intent whatsoever."

Australian Associated Press