The young Magpies trailed inside eight minutes of their Northern Group E encounter at Sincil Bank following Danny Mandroiu's composed finish, before Joe White's deflected strike hit the crossbar for the visitors.

After a spirited second-half display from United's youngsters, Freddie Draper's strike in the closing stages confirmed maximum points for the League One side.

Newcastle headed into the cup contest unable to progress into the knockout stages after losing on penalties to Doncaster Rovers, following a goalless draw, before suffering a 2-0 defeat against Barnsley last month while Lincoln, who lifted the EFL Trophy in 2017/18, required a minimum of two points to book their spot in round two.

Elliott Dickman made five changes to the side which claimed a 2-1 away win at Aston Villa on Friday night as 19-year-old right-back Joe Oliver and Liverpool-born striker Cameron Ferguson, son of former Magpies forward Duncan, were handed their first starts of the 2022/23 campaign at under-21 level.

Charlie Wiggett, who joined the Magpies' youth set-up from Chelsea in the summer of 2021, as well as Kyle Crossley and Jordan Hackett, who both signed their first professional contracts with Newcastle in July 2022, were also named in the starting eleven.

United's second-string were fortunate not to concede after two minutes as Jude Smith's intended clearance from goal was blocked by Ben House but the ball landed kindly into the goalkeeper's arms.

In the 8th minute, Lincoln opened the scoring through Mandroui. After Jordon Garrick dispossessed Alex Murphy inside the penalty area, the winger teed up the Irish forward who slotted the ball into the far left-hand corner.

United's youngsters went in search of a quick response as White went narrowly close to levelling the contest as the Carlisle-born teenager, who signed a three-year contract with the Magpies in March 2022, advanced forward before his deflected shot from the edge of the penalty area looped onto the crossbar before bouncing out for a corner.

Smith, who joined the Magpies from Scottish League Two side East Fife in August, prevented the Imps from doubling their advantage as the Coatbridge-born goalkeeper parried away Charles Vernam's stinging drive before the loose ball ricocheted off Garrick into the net, but the Swansea City loanee had strayed into an offside position.

Crossley, who scored on his debut for Newcastle's under-21 side at the age of 16 against Crystal Palace in April 2021, had an opportunity to draw Newcastle level after capitalising on a loose throw-in but, after driving dangerously towards goal, the 18-year-old left winger drilled his effort wide of the target.

In the second-half, Newcastle made a double substitution as Josh Scott, who scored three goals in his previous three Premier League 2 matches, and striker Isaac Westendorf were deployed from the bench and the latter almost made a bright impact.

The Bremen-born forward collected Jamie Miley's pass before racing towards goal but the 21-year-old's strike was held by Lincoln goalkeeper Jordan Wright.

Jay Turner-Cooke, who joined Newcastle from local rivals Sunderland in January 2021, went close to levelling the match as the 18-year-old midfielder's effort from distance curled narrowly wide of the target.

James Huntley, who signed his first professional deal with his boyhood club last summer, was introduced from the substitutes' bench and fired his attempt over the crossbar after Westendorf managed to tee up the central midfielder from the left byline.

Smith denied Freddie Draper from extending the hosts' advantage after the substitute had raced in-behind the United defence before his resulting effort was blocked by the legs of the Newcastle goalkeeper.

However, in the 85th minute, Smith was unable to deny Draper for a second time after advancing beyond Oliver before his powerful low effort crept past Smith.

Newcastle United Under-21s return to Premier League 2 action on Sunday, 23rd October when they host their Southampton counterparts at Whitley Park (kick-off 2pm BST).

Newcastle United Under-21s: Jude Smith, Joe Oliver, Niall Brookwell, Charlie Wiggett, Alex Murphy (c), Jamie Miley (James Huntley 68), Jay Turner-Cooke, Joe White, Kyle Crossley (Josh Scott 58), Jordan Hackett (Matt Bondswell 68), Cameron Ferguson (Isaac Westendorf 58).

Subs not used: Will Brown, Nathan Carlyon, Michael Ndiweni.