National League side Barrow pulled off a major FA Cup second-round upset as they came from behind to win 2-1 at League One Bristol Rovers on Sunday.
Byron Harrison netted twice to turn the tie around, swiftly cancelling out Rory Gaffney's 10th-minute opener for the hosts before adding a second strike against the Pirates after 61 minutes.
Sixth-tier Curzon Ashton had looked set to cause a shock as well but suffered heartbreak against AFC Wimbledon, after they went from 3-0 up to losing 4-3 in the closing stages of a crazy match at the Tameside Stadium.
Adam Morgan completed a hat-trick in the 62nd minute to seemingly secure a fine victory for the hosts, but their League One opponents suddenly drew level late on following goals from Tom Elliott, Dominic Poleon and substitute Tyrone Barnett in the 80th, 81st and 82nd respectively.
And Elliott then headed in his second goal of the day in stoppage time to send his side through.
League Two Cambridge United recorded a comprehensive victory over opponents from a division above, thrashing Coventry 4-0 at home with Luke Berry scoring all of the goals.
Midfielder Berry notched a first-half hat-trick - the middle effort being a penalty - before adding his fourth towards the end.
Eastleigh of the National League secured a 3-3 draw at home against sixth-tier FC Halifax Town thanks to Mikael Mandron's 90th-minute leveller.
Mandron had opened the scoring, before Jordan Sinnott, Scott Garner and Richard Peniket scored in quick succession after the break to put the Shaymen 3-1 up. Scott Wilson subsequently pulled a goal back, with Mandron then ensuring both sides' names will be in the hat for Monday's third-round draw.
Another non-league side who will feature in the draw are seventh-tier Stourbridge, whose home tie against Northampton was postponed due to a frozen pitch.
Braintree fought bravely at Millwall before eventually suffering a 5-2 defeat.
Michael Cheek gave the National League visitors an early lead, but Millwall replied swiftly through a Harry Smith double and Shane Ferguson's effort, before Jack Midson made it 3-2 10 minutes prior to the break.
Smith then completed his hat-trick soon after the interval, and Aiden O'Brien added a strike at the death.
Woking, another National League outfit, had Charlie Carter sent off as they lost 3-0 at home to Accrington.
Carter was dismissed shortly after Stanley went 1-0 up through Billy Kee, who then struck again with half-time approaching, John O'Sullivan adding his name to the scoresheet in the second-half.
Elsewhere, Notts County snatched a replay against Peterborough as they battled back to seal a 2-2 draw at home.
Posh appeared to be cruising after early goals from Leonardo Da Silva Lopes and Gwion Edwards, but then Adam Campbell made it 2-1 and the visitors had Lee Angol sent off in stoppage time at the end of the first half, with Louis Laing subsequently drawing the tie level in stoppage time.
Bolton advanced with a 3-2 win over Sheffield United at the Macron Stadium, where Gary Madine and Sammy Ameobi put the home side in charge.
Paul Coutts responded for the Blades but Josh Vela then netted Wanderers' third, with Jack O'Connell's effort soon after proving only a consolation.
The day's other second-round tie saw Port Vale thump Hartlepool 4-0 at home.
Vale were 3-0 ahead by half-time courtesy of efforts from Rigino Cicilia and Alex Jones either side of a Michael Woods own-goal, and Ryan Taylor scored a penalty early in the second half.
The draw for the FA Cup third round takes place at 7.10pm on Monday - follow it live with our blog.