Rotherham hit a dramatic last-minute winner to force extra-time on the way to a 4-2 win over Sutton in the Papa John's Trophy final at Wembley.
Matt Gray's Sutton - who won the 2020/21 National League title and are firmly in the mix for promotion from League Two - looked on course to continue their fairytale first season as an EFL club after Donovan Wilson and Craig Eastmond struck either side of a Ben Wiles stunner.
But in the final minute of second half stoppage time, the Millers forced a further 30 minutes, when Jordi Osei-Tutu found space in the box to equalise.
That killed their opponents' spirit and, with further goals from Chiedozie Ogbene and Michael Ihiekwe, Rotherham secured the trophy for the second time in their history, following their Auto Windscreens Shield triumph in April 1996.
At first, it appeared as though Sutton - facing the League One leaders for the first time - would be forced to sit back, soak up the pressure and hit their opponents on the counter. But it soon became clear that was not the way proceedings were going to unfold.
They should have been in front after 13 minutes, when Will Randall jinked out of the way of a sliding defender and fired the wrong side of the left-hand post, but on the half-hour, they were.
David Ajiboye's cross was controlled by Randall and, after he had squared for Wilson, the Sutton striker took a neat touch and fired through a crowd, past goalkeeper Viktor Johansson and into the bottom right corner.
Groans of frustration in the Rotherham end began to grow after that, but the mood was lifted just before half time, when Wiles arrived in the D, seized a Joshua Kayode knock-on and caressed a beautiful equaliser in off the underside of the crossbar.
It was the Millers' 24th goal in the competition, which set a new record for the most by a side in a single season, but that mattered little after the break when Sutton stalwart Craig Eastmond - the former Arsenal midfielder who has been at Gander Green Lane since 2015 - converted Ajiboye's pull-back three minutes after the restart.
For so long, it looked as though the passive Millers would be forced to concede defeat, but they turned the screw as the full time whistle approached and got their reward at the death, when Osei-Tutu steadied himself to find the net to force extra-time.
And they were not prepared to rest on their laurels thereafter. Ogbene thundered in a stunning shot from 25 yards to settle any lingering nerves, before Ihiekwe nodded home an inswinging Shane Ferguson corner to make sure of what turned out to be a comfortable victory.