Colyer, who played 10 games last season, gained a reputation as a super-sub in his second season and was expected to gain selection for the season opener against North Melbourne.
"It’s disappointing news for Travis so close to Saturday nights game," football operations manager Paul Hamilton told the Essendon website.
"Travis has had a big pre-season, and was really looking forward to playing a role in our first match against the Kangaroos.
"Travis is remaining positive and while he won’t be able to partake in full-scale training, he’s buoyed by the fact he will be able to maintain his fitness levels through running."
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