The 21-year-old was an 82nd-minute substitute at the Keepmoat Stadium before starting here against Darlington at Blackwell Meadows, and his strike, along with Dylan Stephenson's late brace, gave Chris Hogg's young Magpies victory against a side hoping to challenge for promotion from the National League North in the season ahead. 

Allan had already had the ball in the net early on, back-heeling home from close range after a goalmouth scramble, but was deemed to be in an offside position as the chance fell to him.

Darlington - wearing a Brazil-style yellow and blue change kit rather than their normal black and white home colours to avoid a kit clash - then came close twice through former Magpies youngster Luke Charman.

First, he headed wide from a wicked Will Hatfield delivery, then he was denied by an excellent block from Remi Savage, the defender who joined United from Liverpool last month.

Quakers full-back Joey Hope also threatened with a cross-cum-shot from range which went off target before Newcastle took the lead.

It was a strong run and a smart, low finish from Allan, who spent part of last season on loan at Accrington Stanley after signing a new deal with the Magpies and made his first-team debut against Rochdale in the Emirates FA Cup in January 2020.

There was still time for Joe Wheatley to shoot wide for Darlington before half time, with United fielding a completely different XI for the second period. 

In the 54th minute, Darlington equalised as a Hatfield free kick was seemingly forced home by Lexus Beeden, although Quakers' captain Hatfield was initially credited with the goal by the Blackwell Meadows tannoy announcer. 

Rosaire Longelo saw a fierce shot well held by Darlington substitute goalkeeper Lucas Martin, who replaced Tommy Taylor shortly after an accidental clash with Stephenson, and Joe White fired wide a few minutes later, while the hosts responded with efforts from Hatfield and new signing Kevin Dos Santos, but neither found their target.

But in the 81st minute, Longelo played a fine ball into the path of Stephenson, who slid in with real determination to restore United's advantage, before the 18-year-old - who signed his first professional contract with Newcastle this summer - added another in the final minute after an incisive Magpies move. 

Newcastle United Under-23s (first half): Will Brown, Joe Oliver, Matt Bondswell, Remi Savage, Oisín McEntee, Niall Brookwell, Lucas de Bolle, Tom Allan, Cameron Ferguson, Stan Flaherty, Adam Wilson

Newcastle United Under-23s (second half): Max Thompson, Josh Scott, Brad Cross, Charlie Wiggett, Rosaire Longelo, Dylan Stephenson, Nathan Carlyon, Josh Stewart, Jack Young, Joe White, Jay Turner-Cooke

Photograph courtesy of Andy Futers Photography/Darlington FC