Motlop, who signed a two-year deal to remain with Carlton, suffered the injury at training on Monday. Archer, who has had an injury-riddled career so far, received the results of scans after going down with a right knee injury at training on Saturday.
Blues football boss Chris Davies said Motlop was a resilient character who would now concentrate on his rehabilitation.
Jesse Motlop celebrates kicking a goal for the Blues.Credit: Getty Images
“Jesse has put in plenty of hard work in the pre-season, so we are really feeling for him at this time,” Davies said.
“While there is understandable disappointment right now, Jesse is the ultimate professional, who possesses great resilience, which will help as he moves through the recovery process.”
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The Blues have Elijah Hollands and Will White training with the club in the hope of gaining a spot on the list via the pre-season supplemental process.
Archer, the son of North Melbourne great Glenn, played just three matches last season due to suspension and injury.
Adelaide youngster Tom Cochrane also suffered a “significant” hamstring injury on Monday which will force him to miss the start of the season.
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