Swindon Town 2-4 Brighton & Hove Albion (aet)
Jake Forster-Caskey scored two extra time penalties as Brighton won at League One side Swindon Town to reach the third round of the Capital One Cup.
Rohan Ince scored a stunning 20-yard volley for the Championship side after 10 minutes but Louis Thompson equalised at the start of the second half.
In extra time, Adrian Colunga put the Seagulls back in front from close range before Forster-Caskey made it 3-1.
Yaser Kasim pulled a goal back before Forster-Caskey's second late on.
Colunga, who signed from Spanish side Getafe on Monday, made a quick impact when his pass set up Ince to smash in the opener.
Thompson guided in a deserved equaliser seconds after half-time before Lewis Dunk hit the crossbar for the visitors.
Swindon, who were down to 10 men in extra time when former Brighton man George Barker went off with a shoulder injury after they had used all three substitutions, fell behind in the 99th minute when Colunga turned in Adam Chicksen's cross.
Jordan Turnbull brought down Colunga for Forster-Caskey's first. And the penalty-taker was brought down himself by Nathan Thompson, who was red carded, for his second to wrap up the win after Kasim's solo effort had made it 3-2.
Brighton travel to Burton in the third round.
Swindon manager Mark Cooper: "I thought our team were sensational and if I was a Premier League manager I would sign Yaser Kasim straight away.
"They deserve every plaudit they get. They will say what a fantastic football team Swindon have. Our players were incredible to play the football they did against a Championship side.
"You take everything as a positive. The thing that stands out for me was nearly every Brighton player came up to find me and said what a fantastic football team you have."
Brighton manager Sami Hyypia: "It was very difficult for (Colunga) as we only got international clearance at the last minute for him at the team meeting before the game.
"When a striker scores a goal it is good as it gives them confidence. It was difficult to communicate with him because he doesn't speak English, but I can probably say 'well done' in Spanish.
"We knew Swindon were a good team but I was surprised how good they are. They played some good stuff and made it very difficult for us."