Given his history of lower-body injuries and how painful the play looked, the severity could have been much worse.
The 25-year-old winger exited the game with 4:40 minutes left in the second period after he delivered a hit on Jacob Bernard-Docker. Allison went down writhing in pain and needed assistance to leave the ice after a stoppage of play.
He didn't return to the game and finished with seven hits in 8:14 minutes.
Allison dealt with two ankle injuries and an MCL sprain over the past two seasons. He also overcame an ACL tear during his four-year collegiate career at Western Michigan.
With Allison out, Kieffer Bellows will get an extended opportunity to make an impression on head coach John Tortorella and his staff. The 2016 first-round pick of the Islanders was claimed off of waivers Oct. 27.
"I think the big thing is I just want to be a power forward," Bellows said last month. "I think that's kind of the role that I see myself as, a power forward that scores goals, has good offensive flair, but can be trusted defensively, as well."
Max Willman is set to get his first look of the season Tuesday as the Flyers face the Blue Jackets in Columbus, Ohio (7:30 p.m. ET/ESPN+, Hulu). The 27-year-old forward was called up Monday from AHL affiliate Lehigh Valley, while Tanner Laczynski was loaned to the Phantoms.
In other roster matters at forward, Patrick Brown and Artem Anisimov have reported to Lehigh Valley.
Brown, a 30-year-old center, is there for a conditioning assignment after recovering from a back injury.
Anisimov, a 34-year-old center on a professional tryout with the Flyers, is joining the Phantoms on a PTO. His training camp ended after the Flyers' preseason opener when he suffered an injury blocking a shot.
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