Homegrown pair Sean Longstaff and Cal Roberts – the latter making his first start for the club – gave the Magpies a commanding lead inside the first 25 minutes, but they were pegged back before the break by another United Academy graduate, Adam Armstrong, and defender Darragh Lenihan.

Rovers shaded a rather less frantic second half before coming close to taking the lead in the first period of extra time, with Bradley Dack failing to hit the target with just Freddie Woodman to beat.

Sparked back into life, Newcastle quickly re-took the lead through Joselu, who struck for the first time for United away from St. James’ Park. Substitute Ayoze Pérez then put the outcome beyond doubt, setting up a meeting with fellow Premier League outfit Watford in the last 32.

The Magpies could hardly have got off to a better start, taking the lead after less than 60 seconds – their quickest goal of the campaign. After a throw on the left, lone frontman Joselu teed up Longstaff 20 yards out, and the youngster took a couple of touches to set himself before thumping the ball past David Raya – albeit with the help of a wicked deflection.

Though Rovers looked to assert themselves in the final third after that, United continued to look the most threatening – particularly on the break. Matt Ritchie called Raya into action with almost a quarter of an hour played, gathering Jacob Murphy’s cutback before taking aim at the Spanish ‘keeper from a tight angle.

However, Newcastle didn’t have long to wait for their second. Midway through the half, Murphy stung the palms of Raya but managed to pick up the pieces close to the byline. He paused for a moment before picking out Roberts, who got across Rovers’ Lewis Travis and side-footed the ball into the near corner of the net.

With United looking completely in control, Fabian Schär – deployed in a central midfield role on the night – then headed Ritchie’s out-swinging corner over the crossbar. However, they were undone out of nowhere just after the half-hour mark, as Armstrong latched onto Danny Graham’s threaded pass before stabbing the ball past ex-colleague Woodman.

A warning shot arrived two minutes later, when Lenihan rose highest from a Harrison Reed corner and narrowly cleared the crossbar. United failed to learn their lesson, however, and having got themselves into such a promising position early on, their advantage disappeared completely just before the break, when the defender met another Reed corner and powered his header beyond Woodman.

Rafa Benítez made a defensive switch at the interval, bringing Jamaal Lascelles on in place of Ciaran Clark. However, the Magpies’ skipper lasted less than a quarter of an hour before having to go back off with a hamstring injury. In between, Ritchie nearly restored United’s lead with a piledriver from 20 yards, while a sliced Lascelles clearance – which came several minutes after he started hobbling – nearly allowed Ben Brereton in for Blackburn.

After a more subdued spell, Newcastle nearly got back in front through substitute Isaac Hayden – Lascelles’ replacement. The midfielder got across his marker and connected with Ritchie’s corner from the left, only to see the ball rebound agonisingly off the near post.

Blackburn boss Tony Mowbray introduced attacking midfielder Dack – Rovers’ goalscorer in the first tie at St. James’ Park – in the closing stages, a decision which lifted his side. They looked the more likely to nab a winner prior to the 90-minute mark, with Dack firing wide after allowing a long throw to run across his body, and another substitute, Craig Conway, forcing Woodman into a low stop.

The home side continued to look the more likely as extra time began. Joe Nuttall headed wide from a fine Amari’i Bell cross, before the lively Dack squandered a great chance after being set up by Conway, rolling the ball harmlessly off-target from just inside the penalty area – though, to the United ‘keeper’s credit, Woodman was quick off his line.

Newcastle, in contrast, offered almost nothing during those first 15 minutes, but with virtually the last kick before the whistle, they got themselves back in front through Joselu. Raya failed to hang on to Schär’s hopeful effort from range, and the Spanish frontman was on hand to force the ball over the line.

And, two minutes into the second period, the Magpies wrapped things up. Ritchie sent Pérez flying down the right flank, and the forward stepped inside before rifling an unstoppable shot past Raya.