Watch: Bobby Ryan goes after Senators prospect for hit on MacArthur

This isn't the best way to endear yourself to potential teammates.

Patrick Sieloff, a 22-year-old defenseman hoping to crack the Ottawa Senators, caught veteran Clarke MacArthur with a dangerous hit Sunday at training camp, and Bobby Ryan immediately came to MacArthur's defense.

Ryan clearly wasn't pleased with the blindside check at the time.

MacArthur was later diagnosed with a concussion, a troubling prognosis considering he missed virtually all of last season with concussion-related symptoms.