The unlikely victory ended a 14-game winless streak for Chivas, which despite the triumph remained stuck in last place in the Western Conference seven points behind San Jose.
The chances for a positive Chivas result seemed remote when Eric Avila was handed a direct red card in the 25th minute by referee Sorin Stoica, the second controversial ruling Stoica has made in less than a week.
Avila was sent off for a sliding tackle on Toronto's Darel Russell. Replays indicated Avila attempted to pull up before making what appeared to be minimal contact.
Stoica also handed a red card in the closing minutes of a game last Saturday to Seattle's Osvaldo Alonso, a decision that was rescinded by Major League Soccer on Wednesday. That decision will allow Alonso to take part in Seattle's meeting with Colorado next Saturday.
The goal by Torres came from outside the box off an assist by Tristan Bowen.
Chivas won three of its first five games this season before suffering its long drought. Its last win had come on March 30 against Vancouver.
Toronto fell to 2-14-4 and is in next-to-last place in the Eastern Conference.