''We're behind the 8-ball,'' said Portland head coach Caleb Porter. ''There are plenty of examples of teams that have started out slow. But in the end, we're not where we want to be, at this point, and we need to step it up.''
Torres scored off a cross from Leandro Barrera for his fifth goal of the season for Chivas USA (1-2-3).
It was situation Porter had hoped to avoid. ''Torres was the key guy, we talked about it all week,'' Porters said. ''He's good at getting into spots to score.''
Will Johnson opened the scoring for Portland in the seventh minute. He scored for the first time this year after finishing with nine goals last season.
Maximiliano Urruti forced a turnover and got the ball to Darlington Nagbe, who slid a pass between two defenders and into enough open space for Johnson to run into it and knock a right-footed shot past Dan Kennedy.
According to Chivas USA head coach Wilmer Cabrera, Portland's goal was helped by an error in footwear selection.
''We picked the wrong shoes,'' Cabrera said. ''Sadly, Carlos (Bocanegra) slipped, and he realized he needed to change his cleats. And then he was on the sideline in the moment that we conceded that goal. They were playing with 11, we were playing with 10, in that moment, they took advantage and they scored a goal.''
Portland had a late chance when Johnson had a free kick just outside the penalty area, but his shot hit the post and went out of bounds.
Chivas USA's Thomas McNamara was taken off on a stretcher in the 64th minute with what appeared to be a serious knee injury. The midfielder crumpled to the ground while running with the ball and trying to avoid Portland defenders.
''Sadly, it looks pretty bad,'' said Cabrera. ''Right now, we have to confirm, but it's not promising for us. That's the sad part of this game.''
Portland had its 55th straight sellout with a crowd of 20,814.