Reilly O'Connor scored twice and added two assists, and eight different Warriors scored to give Whitby a 2-1 advantage in the best-of-five series for Canada's box lacrosse junior championship.
Whitby took Game 1 on Thursday, but lost Game 2 on Friday. Game 4 will be played Sunday at Queen’s Park Arena.
New Westminster opened the scoring on an unassisted goal by Brendan Ranford at 5:49 of the first period, but the lead was short-lived as Whitby stormed back with three unanswered goals in the opening period.
The Warriors blew the game open in the second period, scoring seven goals, including a short-handed tally by MacDonald.
Josh Byrne scored two for New Westminister and Luke Gillespie added the other Salmonbellies goal.
Fights broke out in the second and third periods and a total of 10 game misconducts were handed out between the teams. Whitby received 117 penalty minutes on 24 infractions while the Salmonbellies were given 107 minutes on 22 separate penalties.
Whitby goalie Alexis Buque made 34 saves and back-up Josh Delves played three minutes, stopping both shots he faced. Frank Scigliano made 34 saves for New Westminster before being replaced by Michael Flintoff, who allowed one goal on two shots.