Swansea out, Arsenal win on pens
Capital One Cup holders Swansea crashed out of the competition after a 3-1 loss at Birmingham but Arsenal, Newcastle and Stoke all progressed.
Arguably the biggest shock of this year's competition came at St Andrew's, where Birmingham secured a victory against the Swans.
After a first half in which Wilfried Bony and Alejandro Pozuelo hit the post in quick succession, Blues appeared a different animal after the break.
Dan Burn headed home his first goal for the club in the 56th minute, before Matt Green added a second from close range soon after.
Inspired by winger Chris Burke, who played his part in all three goals, Tom Adeyemi also got in on the act with his maiden goal late on - with Bony netting a consolation with virtually the last touch.
Arsenal beat West Brom 4-3 in a penalty shootout after their third-round tie finished 1-1 after extra time.
German midfielder Thomas Eisfeld slotted in what was his first Gunners goal on his maiden start to give the visitors the lead.
West Brom equalised in the 71st minute when Saido Berahino, scorer of a
hat-trick in round two, headed past Lukasz Fabianski from close range.
Baggies substitute Morgan Amalfitano hit the bar in extra time but the teams
could not be separated over 120 minutes.
In the shoot-out, West Brom initially had the advantage after Luke Daniels
saved Serge Gnabry's effort, but misses from Craig Dawson and Amalfitano allowed Nacho Monreal to seal victory for the away side.
Papiss Cisse's first goal since April helped ease Newcastle to a 2-0 victory over Leeds.
The Senegal international's drought finally ended 31 minutes into a pulsating encounter when he powered a header past goalkeeper Paddy Kenny to end a run stretching back to the 1-1 Europa League draw with Benfica on April 11.
However, the tie remained in the balance until deep into the second half when strike partner Yoan Gouffran blasted home to wrap up a 2-0 win over the Sky Bet Championship side.
Stephen Ireland marked his first Stoke start with a goal in the 2-0 victory at Tranmere.
One of seven changes made by manager Mark Hughes, the on-loan Aston Villa midfielder put them ahead in the 23rd minute at Prenton Park.
Peter Crouch, making his first start of the season, scored in stoppage time to seal a 2-0 victory which was somewhat harsh on the hosts.