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Colchester United are 11th in League Two
Marine are ninth in Northern Premier League Division One North West, the eighth tier of English football
Elsewhere, Sunderland's focus will be back on promotion from League One after they suffered a 1-0 defeat against Mansfield, whose new boss Nigel Clough watched on.
Luke Jephcott's 60th minute effort was enough to send Plymouth, League One's eighth place club, through at the expense of Charlton, third in the table.
Danny Newton (98 mins)
Heartbreak for Concord.
Eight minutes into extra-time and League Two Stevenage have gone in front through substitute Danny Newton.
FC United of Manchester v Doncaster Rovers (17:30 GMT)
FC United of Manchester: The story of their most famous FA Cup night
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It'll be a huge shock if the club founded in 2005 beat Doncaster, who sit ninth in League One.
Brackley Town 3-3 Bishop's Stortford
So nearly the lead for Brackley Town!
Lee Ndlovu one-on-one with the keeper...
...puts the ball over.
A tired shot.
FC United of Manchester v Doncaster (17:30 GMT)
BBC Two
We're about 25 minutes away from our final tie of the day between non-league FC United of Manchester and League One Doncaster Rovers.
It's live on BBC Two from 17:15 GMT. Time to grab a quick cuppa and then settle back.
Kabongo Tshimanga
Kabongo Tshimanga tucks in from the spot after he is brought down in the area.
Some very tired legs across our ties that have gone into extra-time.
I've seen a number of games stopped on the monitors in front of me. Cramp is starting to set in.
Most of our extra-time ties have now restarted. Quick turnaround eh? We can hardly keep up!
Oh, and we've also got extra-time in the all non-league tie between Brackley Town and Bishop's Stortford. It's 3-3 there.
Ipswich 2-2 Portsmouth
Extra-time at Portman Road.
Great fightback by Ipswich who trailed 2-0 after 13 minutes before hauling themselves back into the all-League One tie.
They hold on! National League North Darlington have done it.
Adam Campbell is the hero for Darlo today.
And Concord also force extra-time. What a story.
Colchester United 1-1 Marine
AFC Marine hold on. Stick with us, we're going to extra-time.
Cheltenham Town 3-1 South Shields
The Northern Premier League did manage to equalise after going a goal down in the first half but eventually succumbed to the Robins.
Hopefully the Mariners enjoyed their FA Cup first-round debut.
Swindon Town 1-2 Darlington
A few seconds to go, can Darlo hold on?
Stockport County are one win away from joining Premier League clubs in the draw for the third round.
Terrific result.
And that penalty's the last kick. A classic cup-set. Dagenham & Redbridge are in the second round.
Brilliant.
Decent scalp that for King's Lynn Town.
Mitch Brundle
Daggers' Weston is hacked down in the area and Mitch Brundle makes no mistake from the spot.
Scenes in the dugout for the non-leaguers.
Veteran defender Peter Clarke has put Tranmere 2-1 up against Accrington Stanley with only a few minutes left at Prenton Park.
Lincoln City have scored two more and are hammering Forest Green 6-1.
Banbury Utd 1-2 Canvey Island
You can definitely call this a mini-shock as Canvey Island - 15th in the Isthmian League North Division - defeat Banbury United, a tier above, thanks to goals from Connor Hubble and Elliott Ronto.
Can Canvey now match their efforts of 2002, when they reached the third round?