It was first reported by The Herald Sun on Friday night that Kelly was a close contact of positive COVID cases in his family.
Under current Australian federal government health policy, close contacts are defined as household members of a confirmed positive case, or those who have been in an indoor environvment with a confirmed posisitve case for at least four hours.
It was understood at that stage he hadn't tested positive to the virus.
That has now changed, with Code Sports reporting Kelly tested positive on Monday morning, meaning he will miss the season opener and only be cleared to return to training the day after the game against the Gold Coast Suns.
“He’s under the health and safety protocols at the moment,” Eagles coach Adam Simpson said on Monday.
“You’re going to find this happens a lot, with every club but the two Western Australian clubs in particular.
“We’ll announce at team selection whether he’s available or not.”
Kelly's delay to playing games for the Eagles this season is the last thing the club needed, with the club already facing a long injury list for Round 1.
All of Oscar Allen (foot), Elliot Yeo (calf), Dom Sheed (syndesmosis), first-round draftee Campbell Chesser (foot) and Jamie Cripps (pectoral) are unlikely to play, while Luke Shuey and Liam Duggan are also racing the clock.