Tranmere Rovers will be in the draw for the third round of the FA Cup after a late equaliser from veteran midfielder Jason Koumas saw the League Two strugglers take Oxford United to a replay.
Cole Stockton's 33rd-minute strike had given the travelling Wirral support a sniff of a rare victory before two goals in five second-half minutes from Tyrone Barnett saw the U's take control at the Kassam Stadium.
However, it was left to Koumas to earn Micky Adams's men a replay at Prenton Park after his shot from the edge of the area proved too much for Ryan Clarke.
They sre joined in the draw by Sheffield United, who needed two second-half penalties from Jose Baxter to help see off the challenge of Plymouth Argyle at Bramall Lane.
Marc McNulty added a third in the 90th minute as the Blades ran out comfortable winners.
MK Dons' cup campaign has come to an end after they lost at home to Chesterfield, with Armaud Gnandulliet netting the crucial goal for the Spireites.
Fellow League One promotion-chasers Preston North End managed to successfully see off Shrewsbury Town after Paul Huntingdon's early goal ensured safe passage into round three for the Lilywhites.
Mansfield Town were moments away from knocking out Cambridge United at the Abbey Stadium, thanks to Tom Champion's own goal.
However, Kwesi Appiah struck deep in second-half stoppage time to earn United a second chance at Field Mill.
Bury's own FA Cup hopes were also kept alive as Daniel Nardiello scored in the 91st minute at Gigg Lane to cancel out Mark Cullen's strike for the Hatters.
Accrington Stanley kept their cup run going after a Tom Aldred goal saw the Lancashire club take Yeovil Town to a replay.
Oldham Athletic's good run at home was dented after Genseric Kusunga put through his own net four minutes from time to give Doncaster Rovers victory at Boundary Park in Paul Dickov's first game against the Latics since leaving the club in February 2013.
Wrexham face Maidstone United on Saturday evening, while 10 further second-round ties take place on Sunday.
Results in full: Accrington Stanley 1-1 Yeovil Town, Bury 1-1 Luton Town, Cambridge United 2-2 Mansfield Town, MK Dons 0-1 Chesterfield, Oldham Athletic 0-1 Doncaster Rovers, Oxford United 2-2 Tranmere Rovers, Preston North End 1-0 Shrewsbury Town, Sheffield United 3-0 Plymouth Argyle, Wrexham E-E Maidstone United
