Chivas midfielder Agustin Pelletieri was ejected in the 13th minute for a studs-up tackle on Vancouver's Pedro Morales.
Erick Torres scored for Chivas (1-0-1) in the 45th minute.
Mauro Rosales sprinted down the middle of the field and fed Torres, who fired a shot on goal. The ball deflected off Vancouver's Jey DeMerit and bounced across the goal line for Torres' second goal of the season.
Vancouver (1-0-1) ultimately capitalized on a Chivas turnover to tie it. Dani Fragoso, who entered the match a minute earlier, lost the ball near the halfway line. Darren Mattocks pounced on it, carried it into the penalty area and fed Manneh, who rifled a shot into the back of the net.