Liverpool manager Rafael Benitez sent out a much-shuffled line-up to face Leeds at Elland Road, and despite a spirited performance from the home side, David Ngog's 66th-minute winner was enough to send his side into the fourth round.
Liverpool struggled to impose themselves on the League One side and Leeds' attacking trio of Jermaine Beckford, Luciano Becchio and winger Robert Snodgrass tormented the visitors in the first half. Becchio was especially unlucky, when he tapped in only to find the assistant had ruled him offside. Replays showed that the striker was just on and boss Simon Grayson continued to question the fourth official on the decision.
Leeds were the better side for the majority of the contest but it was David Ngog who provided the all-important goal for Liverpool, turning smartly before cooly slotting into the bottom corner. It was a body blow to Leeds who struggled to regain their rhythm, with Liverpool holding on to squeeze through.
Burnley's brilliant Premier League start counted for nothing against Barnsley as Hugo Colace's late winner left Owen Coyle's men on the wrong end of an upset.
Hugo Colace headed home in the 75th minute to seal victory in an entertaining game at Oakwell in which the Clarets, losing semi-finalists in last year's Carling Cup, drew first blood through Steven Fletcher only for Jonathan Macken to equalise almost immediately.
Anderson De Silva gave the home side the lead with a super 25-yard strike on the stroke of half-time before Chris Eagles equalised in the 52nd minute, setting up Colace to grab the winner.
Arsene Wenger again used the Carling Cup as a platform to blood his youngsters, and his inexperienced Arsenal side proved too good for Championship leaders West Brom, who had headed into the game with confidence after their 5-0 weekend win at Middlesbrough.
Baggies boss Roberto di Matteo also rang the changes and the result was a comfortable 2-0 victory for an Arsenal side with an average age of just over 20, the Gunners easing through courtesy of second-half goals from Sanchez Watt and Carlos Vela.
Andy Griffin's injury-time winner capped a night of late drama at the Britannia Stadium as Stoke fought back from two goals down to beat Championship side Blackpool 4-3.
Goals from David Vaughan and Billy Clarke gave the Tangerines a two-goal lead, but the home side clawed their way back with a quick-fire burst in the final quarter-hour. Danny Higginbotham, Matthew Etherington and Ricardo Fuller all got on the scoresheet in quick succession. Ben Burgess equalised immediately, only for Griffin's low strike to steal a 4-3 win with virtually the last kick.
Benni McCarthy grabbed the only goal of the game in the 37th minute as Sam Allardyce's Blackburn beat Nottingham Forest at the City Ground.
The Championship club had plenty of chances but McCarthy's fortuitous free-kick was enough for Rovers, who had made ten changes from the side that lost 3-0 to Everton at the weekend.
Portsmouth put their Premier League woes behind them to win at Carlisle, but only after surviving an early scare as veteran Ian Harte's penalty gave the Cumbrians a third-minute lead.
Aruna Dindane equalised in the 26th minute and Danny Webber put Pompey in front before the break. Anthony Vanden Borre made the game safe in the 63rd minute and eased some of the gloom for under-pressure boss Paul Hart.
Gary Cahill's extra-time goal helped Bolton to a 3-1 victory over West Ham, after Kevin Davies had grabbed a late equaliser to cancel out a Herita Ilunga effort.
Gianfranco Zola's men will now have to focus on improving their Premier League form after Cahill's excellent strike and Johan Elmander's finish proved enough to send the Trotters into the fourth round.
Jordan Henderson's early strike for Sunderland set boss Steve Bruce on his way to a comfortable 2-0 victory over his former club Birmingham, with Fraizer Campbell's 23rd-minute second goal all but wrapping things up.