Former United forward Daryl Murphy nodded in with barely two minutes played at the City Ground to give Aitor Karanka’s men the advantage in the second round clash.

With six minutes added time signalled at the end of the second half and Rafa Benítez’s charges seeking a leveller, Salomón Rondón’s first goal in a black and white shirt arrived in the 92nd-minute and looked to have taken the game to penalties.

But two minutes later, Forest retook the lead through Matty Cash’s thumping effort before making it three at the death, as Gil Dias’ delicate finish wrapped it up.

That frantic finale meant Aitor Karanka’s side progressed to the third round at the expense of the Magpies for the second successive season.

It proved to be a difficult night for Newcastle after the hosts made the best start possible. They had threatened even earlier, with Dias testing former Forest keeper Karl Darlow, but it was another player who was facing their old team who dealt the blow. Sam Byram bypassed Kenedy on the right and his fine cross was met by Murphy, who glanced home in front of the United supporters.

Benítez’s men looked to respond, with a Jamie Sterry cross causing momentary problems in the Forest box and Ki Sung-yueng dragging a shot wide from range, but their clearest first half opening came from a corner. Christian Atsu – one of seven players brought into the starting line-up after Sunday’s defeat to Chelsea – swung it in towards Joselu, whose flick dropped agonisingly beyond the reach of both Yoshinori Muto and Federico Fernández, stretching at the back post.

Newcastle rallied at the start of the second period, with Atsu picking out frontman Joselu with a curling cross from the left, but the Spaniard’s header was palmed away by Luke Steele – though the offside flag would have spared Karanka’s side had it found the net.

It took some timely defending from Fernández at the other end to prevent a second Forest goal shortly after. Dias’ shot was parried by Darlow and Murphy was quickest to the loose ball, but the United centre half was quick to slide in and prevent the Irishman from doubling the lead.

Michael Hefele nodded a corner just past the post before debutant Sean Longstaff responded with a shot on goal for the visitors, though it veered off course and looped over after taking a nick off Joselu on its way through.

And Darlow then had to be alert to backpeddle and claw away Joao Carvalho’s chipped cross-shot, which looked to be dropping just under the crossbar until his intervention.

Ayoze Pérez, Jacob Murphy and Rondón were summoned from the bench by Benítez in the final quarter of the match, and it was Venezuelan striker Rondón who had an almost immediate impact, finding space on the right-hand side of the box before blasting home the equaliser via the upright in the second additional minute of six.

But incredibly, the game was far from over. Forest broke down the left and, when Darlow palmed a dangerous low cross away from Murphy, substitute Cash raced in to crash home what looked like the winner.

There was still time for United to see a penalty appeal turned down, as Pérez was sent tumbling in the box by Steele as he looked to run onto a loose ball, but referee Jeremy Simpson was unmoved and waved the appeals away.

And with Newcastle desperately looking to gain ground and progress up the pitch, Kenedy’s error presented Dias with a one-on-one in the 96th-minute. He duly took it, clipping over Darlow to make it 3-1 and cap a remarkable end to a fiercely-contested encounter.