Notts County were beaten 6-5 on penalties in a quite incredible Carabao Cup tie at Glanford Park.
Jorge Grant had given Notts the lead in the first half of normal time but goals from Paddy Madden and Duane Holmes tilted the tie in Scunthorpe's favour.
Shaun Brisley bagged an equaliser in second-half injury time to send the tie into an extra 30 minutes.
And the drama continued as, after Holmes had notched his second, Notts scored a dramatic equaliser through Ryan Yates to send the match to penalties.
Both sides maintained a 100% record in the shootout until Matt Tootle saw his penalty saved, condemning Notts to a 6-5 defeat on penalties.
Kevin Nolan made eight changes with only Brisley, Terry Hawkridge and Jon Stead retaining their places following the opening-day match at Coventry.
Full debuts were handed to goalkeeper Ross Fitzsimons, right back Nicky Hunt and central midfielder Yates.
And Notts showed no signs of struggling to gel, starting the game strongly and nearly opening the scoring with only six minutes on the clock. Hunt's incisive pass released Stead through on goal but he could only roll the ball straight at home goalkeeper Matt Gilks.
Grant was proving himself to be a constant thorn in Scunthorpe's side and, after firing a couple of warning shots wide, the midfielder rattled the bar with a curling effort.
A minute later, however, Grant did break the deadlock. Rob Milsom's superb left-footed cross caused havoc in the Scunthorpe penalty area and the Forest loanee swept the ball home.
Notts had Fitzsimons to thank minutes later when he produced a superb point-blank save to deny Kevin Van Veen.
Scunthorpe were then indebted to their own keeper when Gilks plucked Carl Dickinson's excellent free-kick away from the top corner.
Charlie Goode went into the book for a foul on Jonathan Forte moments before Brisley was inches away from turning Grant's cross home.
But there were to be no more goals before the break, Stead entering the book for a foul on Jordan Clake shortly before the half-time whistle.
There were no Notts changes at half-time and Nolan's defence had to remain resolute when Van Veen's delivery posed problems in the middle. The Magpies managed to hack the ball clear.
And the visitors nearly responded with a second goal when Brisley headed the ball just wide from Hawkridge's floated delivery.
Notts kept up their pressure and were ruing the crossbar once more when Forte's dinked effort from a tight angle bounced up and away to safety.
Scunthorpe had a goal ruled out for offside when Madden turned the ball home from close range.
But the forward's fustrations were short-lived as, after Hawkridge had felled Conor Townsend in the area, Madden struck the penalty beyond Fitzsimons to restore parity.
Notts' first change followed, Matt Tootle replacing Hunt.
But the momentum was now with the hosts, who almost took the lead through a Duane Holmes header. Fitzsimons produced an outstanding fingertip save to divert the ball on to the bar.
Alan Smith replaced Stead with 12 minutes to play and Yates went into the book shortly afterwards for a trip on Holmes.
With the clock ticking down, the next goal would be crucial. Van Veen's eyes lit up when he was released into the area but Fitzsimons narrowed the angle sufficiently to block the Dutchman's effort at his near post.
But, after a sustained spell of Iron pressure, Holmes had his moment when he was threaded through on goal before firing the ball low beyond Fitzsimons.
Elliot Hodge replaced Hawkridge shortly before the officials handed Notts five added minutes in which to find an equaliser.
And they did just that when Brisley, after hitting the post with his initial header from a corner, turned the ball home from close range on the rebound.
Van Veen wasted a superb chance to win it with the last kick of normal time, latching on to a ball over the top but failing to round Fitzsimons.
New EFL rules permit teams a fourth substitution in extra time of the Carabao Cup and Nolan gratefully exercised his right by sending on Curtis Thompson for Grant shortly after play restarted.
Hodge stung Gilks' palms with a well-struck effort and Yates saw a shot deflected wide as Notts looked to stamp their authority back on the game.
And they came within inches of retaking the lead when Hollis struck the ball goalwards following a corner, only for Madden to clear it off the line.
Notts could consider themselves very unfortunate not to be ahead - and their luck got even worse moments later.
With Brisley stranded up front after he had picked up a knock during an attacking set piece, Scunthorpe countered. Hakeeb Adelakun capitalised on the extra space by slipping Madden into the area and the forward made no mistake in making it 3-2 to the hosts.
Madden headed the ball wide and Townsend went into the book for a foul on the lively Hodge as the sides exchanged blows in the second half of extra time.
And the hosts nearly wrapped it up in extravagant style when Holmes weaved his way through the area before supplying Van Veen on the penalty spot. The forward's delightful first-time chip saw the ball bounce back off the bar and splash down into the saturated goalmouth, where Fitzsimons was able to gratefully collect it.
But there was still time for Notts to keep the game alive and they came agonisingly close to another equaliser when Smith outmuscled his defender before rolling the ball across the face of goal. It held up in the soggy conditions and the Iron managed to turn it behind for a corner.
The hosts' relief wasn't to last long, however, as with four minutes left Yates lashed the ball home following a scramble in the middle. The young midfielder required treatment following his heroics but hobbled back into the action.
Two minutes were added on at the end of a quite incredible specatcle but neither side were able to prevent a penalty shootout.
Notts took the first penalty in the newly-introduced ABBA format. Smith smashed the ball home with aplomb.
Madden levelled things up with the next effort before Kevin Van Veen made it 2-1 to the hosts.
Thompson stepped up next for the Magpies, making it 2-2 with a confident strike, and Rob Milsom swung the tie back in Notts' favour with the following penalty.
Adelakun found the net, making it 3-3, before Townsend maintained the 100% record.
Brisley then made it 4-4, with Forte then making it 5-4.
Devonte Redmond had to score to keep it alive and made no mistake, with Scunthorpe Man of the Match Holmes converting his spotkick to make it 6-5 to put the pressure on Tootle.
Something had to give and, unfortunately for Tootle, Gilks got a strong hand to his effort to send the Iron into the second round.