Williamson played in Carlton's 19 point loss against Collingwood in the AFL's round eight clash.

"Willo hyper-extended his back in the fourth quarter. He came off and was a bit restricted when he came back on the ground," Carlton's high performance director Andrew Russell said.

"At this stage he's pretty sore and we don't expect him to play for the next couple of weeks."

Williamson rejoined the main training group at Ikon Park in March after a "frustrating" pre-season.

The up-and-coming defender played 15 AFL games in his debut season in 2017, but back injuries hampered him throughout last year, failing to play a senior game for the Blues in 2018.

Back issues continued to plague the 20-year-old through the most recent pre-season.

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