Panama top Group A on six points from two games, ahead of Martinique and Mexico on three points apiece with Canada propping up the standings after two straight losses.
After their opening loss to Panama, six-times Gold Cup winners Mexico could ill-afford another setback and they attacked Canada from the outset in the second match of the Seattle double-header.
Mexico's second was controversial though, when Canada defender David Edgar was adjudged to have brought down Marco Fabian when it appeared the Mexican had fallen as he stretched for the ball without any contact.
Fabian converted the penalty and Edgar's frustration spilled over in the 67th minute when he kicked out at Jimenez and was lucky to escape with just a yellow card.
Both teams hit the bar late on with Canada's Marcel De Jong's superbly struck 89th minute free-kick finding the woodwork before Javier Orozco's header rebounded off the frame of the goal a minute later.
Martinique produced a big upset on the opening day of the 12-team competition by beating Canada 1-0 and they again showed levels of skill and organisation well beyond expectations for one of the tournament's supposed minnows.
Panama were frustrated and created few chances but the game played at Seattle's CenturyLink Field turned in their favour when Martinique were reduced to 10 men after Jacky Berdix was sent off for a second bookable offence in the 72nd minute.
Five minutes from the end, Panama substitute Jairo Jimenez was brought down inside the box by a reckless Sebastien Cretinoir challenge and Torres squeezed the penalty just past Martinique keeper Kevin Olimpa.
Mexico face Martinique in the final round of Group A matches in Denver on Sunday, after Canada take on Panama at the same venue.
The tournament continues in Miami on Friday with the Group B clashes between Central American rivals Honduras and El Salvador and an all-Caribbean affair as Trinidad and Tobago play Haiti.