The Owls produced the greatest fightback in play-off history on the most incredible night at Hillsborough on Thursday, sealing their place against either Bolton or Barnsley at Wembley on May 29.
Few gave Wednesday a prayer of overturning a heavy semi-final deficit, having been surprisingly thrashed 4-0 in the first leg at London Road last week.
It was a shock result for a team that had set a new EFL record for the most points accrued without securing automatic promotion, ending the regular season on 96 after winning their last four games.
However, Wednesday never gave up hope of potentially joining champions Plymouth and second-place Ipswich and returning to the Championship for the first time since 2021, dominating the second leg on home soil and going 2-0 up inside 25 minutes thanks to an early penalty from Michael Smith and Lee Gregory’s goal.
That early double salvo gave the hosts real inspiration and they scored again with 20 minutes left through Reece James, though still looked set to fall just short before Liam Palmer sparked absolute pandemonium by forcing an extra 30 minutes with the last kick of the 90 deep into stoppage time.
Shell-shocked Peterborough managed to hit back to retake the lead on aggregate through an unfortunate Gregory own goal, but still Wednesday would not be denied as Callum Paterson then made it 5-1 on the night and 5-5 overall to force the lottery of penalties.
Wednesday held their nerve and nailed every spot-kick as Posh defender Dan Butler smashed his against the crossbar to set the seal on one of the greatest comebacks English football has ever seen, sparking a pitch invasion from jubilant home fans.
Afterwards, manager Moore insisted he always believed that a path to Wembley was still possible as he delivered an impassioned post-match speech to his triumphant squad as they take massive momentum into the final next weekend.
“I am absolutely just so proud of every single one of you,” he said. “We had a bit of adversity in the first leg and we knew that we didn’t perform.
“It just goes to show you what preparation does. We’ve prepared all week, the mindset, the mentality and in training. The belief has been there from day dot.
“I cannot commend you all enough in terms of what you’ve just produced out there, it’s absolutely incredible. You really deserve it. I’m absolutely delighted, with what we’ve had to come through this season.
“We’ve got one more. Enjoy tonight, but we’ve got one more. But I’m so proud.”
Speaking to Sky Sports, Moore said: “The key was the fans. I pleaded to them to come out in their numbers and full voice and they've given us that all season.
"They [the players] kept going. Why? Because the fans drove them on. The message to the fans is thanks very much.
"I've slept at night because I knew I had done all I could in preparation. I've kept the belief with the players.
"When you think what we've done from being four goals down. To do it with penalties is remarkable.
"Tomorrow I'll watch the game and then the preparation starts. We enjoy tonight, get up tomorrow morning. We've got a detailed session planned we've had all month."
Long-serving Wednesday captain Barry Bannan also hailed the club’s character after the unsavoury reaction to their first-leg hammering, with Moore having received racist abuse online and vile messages also sent to chairman Dejphon Chansiri.
“Everybody wrote us off. Everybody told us we couldn’t do it but it’s unbelievable,” Bannan told Sky.
“We’ve watched comebacks all week. It was all about believing. When we have the fans behind us, anything is possible.
“It’s the best game I’ve ever played in. I’m so happy because all these lads deserve it. I give everything for this club to get us promoted. Everybody wrote us off but we showed we’re made of strong stuff. We’re only halfway there.
“Those who were booing us last week saying we’re not fit to wear the shirt, have a look at this.
“What he [Moore] has done is unbelievable, to turn around the mindset of the players. I’m so proud of him how he’s handled this week after the racism he’s experienced. That one’s for him.”