Sheffield Wednesday came within a whisker of being humbled at Scunthorpe but grabbed themselves a replay with two goals in the final six minutes.
Scunthorpe boss Brian Laws said: "I'm shell-shocked, happy, dejected and have gone through every emotion.
"We were excellent. Every player played to his capabilities. We should have won this game but if we can put in a performance like this at Hillsborough on a big pitch and in front of a big crowd we should be OK." Owls boss Chris Turner said: "We got out of jail, but to come back from two goals down is some credit to the players who never gave up.
"Everyone in the ground thought we were out but we simply couldn't handle Scunthorpe." Wednesday striker Grant Holt, who gave up a factory job in Barrow to sign professional forms, was the saviour for the Yorkshire side with a brace of goals in the closing stages.
The Owls might have taken an early lead. Adam Proudlock lifted the ball into the middle and Holt's header beat Scunthorpe's Tom Evans but rebounded off the bar.
Wednesday then came under pressure with Leigh Bromby pleased to head away from Steve Torpey before the Iron striker stabbed another effort wide.
Scunthorpe's positive attitude paid dividends in the 33rd minute. Skipper Mark Jackson lofted the ball into the penalty area and Graeme Lee made an error in judgement, heading back and Torpey quickly dispatched the ball home.
Kevin Pressman was kept very busy punching away a ball from his own defence and then clearing from Peter Beagrie.
Scunthorpe almost increased their lead in the 51st minute Richard Kell knocked the ball in and Torpey's header forced Pressman to save at the second attempt.
Wednesday struggled to create any real threat, although Evans did save from Holt, while Lloyd Owusu fired straight at the keeper.
Scunthorpe remained strong adding a second goal in the 71st minute. Beagrie, who had been a constant thorn in the Wednesday defence, crossed from the left and Matthew Sparrow's header hit the upright before Torpey turned the rebound home.
Wednesday pulled a goal back in the 84th minute when Holt poked home from close range and the youngster snatched a replay with his second goal in stoppage time.