Career
He currently plays for the San Jose Sharks of the National Hockey League (National Hockey League). He was drafted by the Sharks 55th overall in the 2012 National Hockey League Entry Draft. Tierney played major junior hockey with the London Knights of the Ontario Hockey League, from 2010 to 2014.
He was signed to a three-year entry-level contract with the San Jose Sharks on April 2, 2013.
After impressing in the Sharks pre-season, Tierney made the opening night 2014-2015 roster in his first professional season. He made his National Hockey League debut with San Jose against the Los Angeles Kings on October 8, 2014.On November 6, 2014, Tierney was re-assigned to the San Jose Sharks" AHL affiliate, Worcester Sharks.