With the Whitecaps trailing 2-0, the 18-year-old Manneh netted his first career MLS goal when he fired in a shot following a tremendous save by Dallas' Raul Fernandez on Camilo's blast seconds earlier.
Camilo followed with the equalizer after Manneh got past three defenders and found the Brazilian alone at close range, whose shot deflected in off defender Jair Benitez.
Vancouver improved to 2-3-3.
Dallas (6-1-2) scored on an own-goal by Vancouver's Andy O'Brien and Matt Hedges also scored for the Western Conference leaders.
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