Collingwood star Steele Sidebottom and teammate Lynden Dunn are currently being investigated by the AFL for multiple breaches of the game's COVID-19 restrictions.
The alleged breaches are said to have taken place following the Magpies' loss to GWS last weekend.
The Magpies confirmed the news via media release on Tuesday evening.
"Collingwood can confirm that players Steele Sidebottom and Lynden Dunn are under investigation for breaches of the AFL's return to play protocols," the statement read.
"Sidebottom and Dunn shared an Uber on Saturday evening and Sidebottom later visited a member of staff who is not living under the game's protocols.
"The breaches were reported to the AFL on Sunday afternoon. The players were interviewed by the AFL yesterday.
"Sidebottom and Dunn will not be permitted to return to the Holden Centre until cleared to do so by COVID-19 testing."
The 'member of staff' referred to in the statement is said to be former teammate Daniel Wells, according to The Age.
The investigations are threatening Sidebottom's place in the Magpies team for their Round 5 clash with Essendon.