He was a valued teammate of Wayne Gretzky when they played together for the Edmonton Oilers and Los Angeles Kings, serving as an enforcer.

He made his NHL debut in October 1983 with the Pittsburgh Penguins but rose to fame after a trade in September 1985 sent him to the Edmonton Oilers.

His arrival and physical presence soon made Edmonton's incumbent enforcer Dave Semenko expendable, and McSorley became known as "Wayne Gretzky's bodyguard".

[4] Back with the Kings, he assisted on Gretzky's goal which broke Gordie Howe's all-time goal-scoring record.

After completing the 1995–96 season with the Rangers, McSorley returned to the West Coast upon being acquired by the San Jose Sharks in August 1996.

Confined to a part-time role in his second stint in Edmonton, he left after one season and signed with the Boston Bruins in December 1999.

Brashear fell backward and hit his head hard on the ice, losing consciousness and suffering a Grade III concussion.

On October 6, 2000, Judge William Kitchen of the Provincial Court of British Columbia found him guilty of assault with a weapon for his attack on Brashear.

He considered purchasing the then struggling Cardiff Devils team with his brother,[10] to become a player-coach and to help to develop interest in the sport in the UK.

From 1995 to 1997, McSorley appeared in four movies in small roles: Bad Boys (1995), Forget Paris (1995), Con Air (1997) and Do Me A Favor (1997).