Teammates threw down after a questionable hit resulted in a concussion

These two teammates must have forgotten they're on the same team when they started brawling

Ottawa Senators Bobby Ryan and Patrick Sieloff got into a scuffle during a scrimmage Sunday after Sieloff laid a hit so menacing on winger Clarke MacArthur that it resulted in a concussion.

Sieloff checked MacArthur against the boards and caught him in the head, drawing an immediate reaction from Ryan, who jumped on the defenseman and started throwing punches. The two had to be separated as MacArthur lay on the ice from the hit. MacArthur appeared in just four games last season due to suffering several concussions.

Teammates Chris Neil and Derick Brassard also took issue with the hit and went after Sieloff at one point.

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The newly acquired Sieloff, a second-round draft pick of the Calgary Flames in 2012, joined the team in June after a trade for right winger Alex Chiasson. Senators general manager Pierre Dorion confirmed that MacArthur suffered a concussion.