The Maple Ridge fell behind 3-1 in the Mann Cup after a second straight loss to the Six Nations Chiefs on Tuesday.
The Chiefs scored an empty-netter to secure another 9-7 win in Ohsweken, Ont.
Ben McIntosh had three goals and two assists for the Burrards. Dan Taylor added a goal and three assists. Jarrett Davis, Connor Goodwin and Luke Gillespie each had a goal and an assist, while Frank Scigliano made 41 saves.
The Burrards outshot Six Nations 51-49, while both teams were 0-2 on the powerplay.
Game 5 on Wednesday, 8 p.m. at Iroquois Lacrosse Arena.
It's another 9-7 victory for the @SN_Chiefs in Game 4. They now have a 3-1 #MannCup series lead. pic.twitter.com/c8XySRfRdA
— Cdn Lacrosse Assoc. (@LacrosseCanada) September 14, 2016