Brighton 2-2 Manchester City (aet - Brighton win 5-3 on penalties)
Manchester City suffered an embarrassing Carling Cup exit after being beaten on penalties by Brighton on Wednesday night.
City survived a scare when Brighton's Steve Thomson shot struck the post before they took the lead through a deflected Gelson Fernandes shot.
Glenn Murray fired in to send the game into extra-time and Joe Anyinsah turned and shot home to put Brighton ahead.
Stephen Ireland slammed in an equaliser but Brighton held their nerve on penalties to send City crashing out.
The result will bring City back down to earth after their recent takeover by the billionaire Abu Dhabi United Group and crushing 6-0 win over Portsmouth on Sunday.
Brighton will now play Derby in the next round.
The Seagulls had gone close when Thomson's shot came back off the post but they had wasteful City finishing and Kuipers to thank for keeping them level until the 64th minute.
Richard Dunne headed over for the visitors, while Michael Johnson skewed a shot wide.
Brazilian striker Jo was denied by Dutch keeper Kuipers before Fernandes failed to head in from a Daniel Sturridge cross.
Fernandes atoned for his miss with the opener when Jo latched on to Ireland's pass on the edge of the area and turned it unselfishly aside for his team-mate.
Kuipers impressively saved from Ireland and Ched Evans and Murray made City pay for their misses when he slotted in after keeper Kasper Schmeichel parried Thomson's effort on 89 minutes.
Anyinsah lashed them ahead five minutes into extra-time but Ireland's reply 10 minutes later forced the shoot-out.
Each of the penalty takers had kept their nerve to score with aplomb before Kuipers saved from Ball and Richards scored the winner.