Mario Balotelli inspired a stirring comeback as Liverpool scored twice in the final few minutes to beat Swansea and reach the League Cup last eight.
The visitors led when Marvin Emnes hooked across Reds understudy keeper Brad Jones into the far corner.
Liverpool rarely threatened until substitute Balotelli guided in Fabio Borini's cross.
Swans defender Federico Fernandez was sent off before centre-back Dejan Lovren headed in the late winner.
Liverpool have made an indifferent start to the Premier League season as they look to replicate last year's second-place finish without the departed Luis Suarez.
Swansea, who are a place above their opponents in the top flight, looked set to eliminate the eight-time winners from the League Cup for the second time in three seasons with Emnes' opener.
Ex-Swans boss Brendan Rodgers watched his current team fall into a familiar pattern of dominating possession without finding a cutting edge.
That was until Balotelli, moved to the bench as one of nine changes to the Reds team which started Saturday's 0-0 Premier League draw against Hull, was introduced with little over 10 minutes left.
The Italy striker has faced heavy criticism for both his attitude and goalscoring record since arriving from AC Milan in August.
But he responded with a cameo performance that brought the Anfield crowd to its feet. His sharp movement led to the equalising goal and, after Fernandez was shown a straight red card for a lunge on Philippe Coutinho, he also unsettled the Swansea defence in the build-up to the winner.
Lovren, whose performances have also been questioned since his £20m move from Southampton, sparked wild celebrations in front of the Kop when he met Coutinho's free-kick to keep alive Rodgers' hopes of winning his first major silverware.