Stephen O'Donnell's 90th-minute goal has helped 10-man Luton Town beat Leyton Orient to reach round two of the Johnstone's Paint Trophy.
Danny Green had given the Hatters the lead at Kenilworth Road before Lloyd James equalised from the penalty spot.
Luton were reduced to 10 when Jack Marriott was sent off late on, but O'Donnell stepped up in the dying moments to send Town through.
Sheffield United needed a penalty shootout to beat League Two high-flyers Hartlepool United after Scott Fenwick cancelled out Ryan Flynn's early opener for the Blades.
Portsmouth are out of the competition after second-half goals from Ryan Harley and Alex Nicholls helped Exeter City to victory at St James' Park.
Plymouth Argyle fought back from two goals down to beat AFC Wimbledon, with Jake Jervis, Ryan Brunt and Carl McHugh on the scoresheet for the Green Army.
Northampton Town are also through to the second round after Marc Roberts scored five minutes from time to see the Cobblers edge a five-goal thriller against Colchester United.
Last year's runners-up Walsall have been knocked out courtesy of a 2-0 defeat at Morecambe, with Tom Barkhuizen sealing progress for the Seasiders.
Izale McLeod was on the scoresheet for Notts County as the Magpies knocked out local rivals Mansfield Town at Meadow Lane.
Swindon Town have progressed after winning a penalty shootout 7-6 against Newport County, while Doncaster Rovers also needed spot kicks to beat Burton Albion.
Yeovil Town are also through at the expense of Barnet, but Millwall needed a stoppage-time winner from Shaun Williams to see off Peterborough United.
Results in full: Hartlepool 1-1 Sheffield United; Luton Town 2-1 Leyton Orient; Accrington Stanley 1-2 Bury; AFC Wimbledon 2-3 Plymouth Argyle; Cambridge United 0-2 Dagenham & Redbridge; Doncaster Rovers 0-0 Burton Albion; Exeter City 2-0 Portsmouth; Millwall 1-0 Peterborough United; Morecambe 2-0 Walsall, Newport County 1-1 Swindon Town; Northampton Town 3-2 Colchester United; Notts County 3-1 Mansfield Town; Port Vale 1-0 Carlisle United; Scunthorpe United 0-2 Barnsley; Shrewsbury Town 2-0 Oldham Athletic; Yeovil Town 1-0 Barnet
