A lengthy ban looms for Xerri, 27, who has been charged with serious misconduct over the incident in Saturday night's game that overshadowed the Kangaroos' 12-point win.
As the Kangaroos play on Good Friday, when Xerri clearly won't be involved, they will quickly have the matter settled at the tribunal on Monday evening.
The incident happened after the Kangaroos big man had complained to an umpire about a blood nose before kicking a goal and clashing physically with McGrath.
Xerri then touched his bloody nose and wiped his hand on McGrath's face.
The ruckman reportedly called McGrath on Sunday to apologise for his actions and is expected to plead guilty to serious misconduct.
A guilty plea would likely be the only way to mitigate what is already expected to be a lengthy suspension.
Saturday night's incident has received widespread condemnation, with AFL chief executive Andrew Dillon on Sunday described the incident as "something that we don't want to see."
Xerri will likely face a far greater penalty than the one-match suspension handed to former Collingwood captain Nathan Buckley after he wiped blood on Geelong tagger Cameron Ling's jumper in 2002.
Ling on Sunday recalled there was "no malice" in the Buckley incident, but declared Xerri's action unacceptable in the modern game.
Essendon great Matthew Lloyd told the Nine Network the suspension had to be at least two weeks, but he wouldn't be surprised if it was three or four weeks.
On Monday, former St Kilda captain Nick Riewoldt told Triple M radio he expected Xerri to be suspended for a month.
That would leave North Melbourne (2-1) without their first-choice ruckman for games against Carlton, Richmond, Brisbane and GWS.
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