A debut goal from Austrian defender Paul Scharner gave Wigan Athletic a 1-0 victory over twice former winners Arsenal in the League Cup semi-final first leg interrupted by a power failure on Tuesday.
Scharner, who came on as a 33rd-minute substitute for the injured Lee McCulloch, rose at the far post to powerfully head in a deep cross from Gary Teale with 12 minutes remaining.
"I was really disappointed with our first-half performance but we responded in the second half and all credit to the players," Wigan manager Paul Jewell told Sky Sports.
"They gave it everything they had and deserved to win. In the second half we were so much better and I was pleased we showed what we are all about."
Promoted Wigan, riding high in sixth place in their first season in the English Premier League, made seven changes for their maiden appearance in the semi-finals of a major cup competition.
Arsenal, who rested captain Thierry Henry, also made four alterations to the team which beat Cardiff City 2-1 in the FA Cup third round on Saturday.
Both sides seemed affected by the wholesale changes with only one shot on target in the opening period.
Teale's low free kick forced a diving side from visiting goalkeeper Manuel Almunia while Freddie Ljungberg missed a good chance at the other end, spooning a 12-metre shot over the crossbar.
FLOODLIGHT FAILURE
A floodlight failure plunged the stadium into darkness and interrupted the match for 15 minutes early in the second half.
"It's a new one for me. I was as surprised as anyone when the lights went out but you have to be guided by the experts," said referee Howard Webb.
Goalmouth incidents were few and far between when the players returned to the field.
Arsenal, who won the trophy in 1987 and 1993, struggled to get in the game and had a narrow escape midway through the second half when Ljungberg nodded a header from Andreas Johansson off the line.
Former Arsenal fan Scharner then struck the only goal to help Wigan take a narrow lead into the second leg at Highbury on January 24.
"Sorry Arsenal," said the 25-year-old defender, who joined Wigan last week from Norway's Brann Bergen for a fee of 2.5 million pounds.
"I'm really happy. Congratulations to the team, the second half was brilliant."
Arsenal manager Arsene Wenger said: "The most disappointing thing was that we didn't score and didn't create a lot of chances.
"In the second half it became more difficult to play and when it became more physical they got on top of us."
The first leg of the other semi-final between Blackburn Rovers and Manchester United is on Wednesday.