Hartlepool cut Blades down to size
Hartlepool caused a Carling Cup shock by dumping Sheffield United out in the first round with a 2-1 win.
The League One side outfought and outplayed their Championship counterparts and took the lead on just six minutes.
Andy Monkhouse fed Joe Gamble and when his shot was blocked by Steve Simonsen, James Brown knocked in the rebound from 12 yards.
In the second half Antony Sweeney, played in by Adam Boyd, was pushed over from behind by Rob Kozluk and Boyd rolled the penalty home as Simonsen went the wrong way.
Ross McCormack came off the bench to help Cardiff to a 4-1 extra-time win at home to Burton.
Jay Bothroyd (17) put Cardiff ahead only for Shaun Harrad to level two minutes later. However, McCormack was introduced for the second half and his brace in extra-time sealed the win before Michael Chopra added a fourth.
Grzegorz Rasiak scored Reading's extra-time stoppage-time winner from close range after the Championship side were taken to the wire by Paul Buckle's brave League Two Torquay.