The two teams are now tied 2-2 in the best-of-seven series for Canada's senior lacrosse championship.
Steven Keogh had a pair of goals and added an assist for Six Nations, while Colin Doyle scored and added three assists. Kedoh Hill and Colin Boucher had singles. Brandon Miller made 47 saves for the win.
Rhys Duch, Jon Harnett and Jeff Shattler supplied the offence for Victoria, while Matt Vinc stopped 38 of 46 shots in 56 minutes of work. Matt Flindell faced no shots during his four minutes in net for the Shamrocks.