The men's soccer team went to Panama looking to extend its lead atop the CONCACAF qualifying group, but a lacklustre effort on hostile ground resulted in a 2-0 loss to a far more energetic opponent.
Rolando Blackburn and Blas Perez each scored for Panama (3-0-1), which regained the top spot in Group C on Tuesday and left Canadian coach Stephen Hart lamenting his team's effort.
"We were second best in everything," said Hart.
"We were second best to close the ball down, second best in the tackle. We didn't pass the ball well or keep possession well and they scored the goal and put us under pressure and I thought our heads dropped way too easily because one goal was scored on us."
Canada (2-1-1) entered the match on a high after beating Panama 1-0 at BMO Field in Toronto on Friday.
But the team looked out of sorts in the first few minutes of the rematch while Panama appeared buoyed by the incredible noise made by the home supporters at the Estadio Rommel Fernandez.
Then, six minutes in, the lights went out.
A bank of lights in the stadium's north end went dark and remained that way for about 14 minutes. When play resumed, Canada had taken out star striker Dwayne De Rosario due to a knee injury that he suffered on an earlier tackle.
The delay provided an opportunity for the Canadian medical staff to work on De Rosario, but in the end they had to replace him with Tosaint Ricketts.
"It might be an (medial collateral ligament injury)," said Hart. "We don't know. We have to do an MRI."
With Canada's best striker out of the game, Panama smelled blood. Blackburn struck in the 23rd minute after rising above some suspect Canadian marking to head in the ball just inside the post.
"No excuse," said Hart. "You're going to come down here. You're going to have to try and get points on the road and the way we started and the lights going out and losing Dwayne we were really lethargic overall and we played the price for it."
Just minutes after play resumed, Canada got a terrific chance when Marcel de Jong had a shot from the side flash across the face of goal and go wide.
Not to be outdone, Panama's Alberto Quintero skillfully eluded both David Edgar and Kevin McKenna before unleashing a powerful right-footed shot that forced Canadian goalkeeper Lars Hirschfeld to make a diving save to his left.
Coming out of the locker-room in the second half, Canada quickly won a few corner kicks in pursuit of an equalizer. Those came to nothing and in the 57th minute, Panama doubled their advantage.
Quintero led an attack on the left wing and easily evaded a sliding Edgar tackle. Hirschfeld raced off his line to try to cut down the angle but Quintero cut the ball back and Perez was there to stab it home from close range.
The two goals were the first Canada has conceded in four games of the third round of qualifying.
"I think we've defended really well as a team. Today we didn't do that," said McKenna. "We know we were getting pulled out of position and they watched the tape and they saw the way we play and they exploited those situations and they were better than us."
Meanwhile Honduras beat Cuba 1-0 to move to second place in the four-team group. The result dropped Canada to third on goal differential.
Canada hosts Cuba (0-0-4) next month before facing Honduras (2-1-1) on the road. Only the top two teams of the group move on to the final round of World Cup qualifying.
Canada is trying to return to the World Cup for only the second time. The team last reached soccer's biggest stage in 1986, and haven't made it to the final round of CONCACAF qualifying since 1998.
Midfielder Patrice Bernier said Canada only has itself to blame for squandering first place in the group so quickly.
"Maybe we weren't all on the same page and that creates some gaps but energy wise we can't afford to have these types of performances if we want to keep going to the next round," said Bernier.