Pompey Academy left it late to book a date with Newcastle United.
Matt Mayes and Tommy Scutt struck in the final 10 minutes to see off Metropolitan Police tonight at Fratton Park.
It was an FA Youth Cup match of few goal-scoring opportunities.
Yet just when it appeared to be heading into extra-time, Mayes’ header broke the deadlock on 80 minutes.
Midfielder Scutt sealed the 2-0 scoreline one minute into stoppage time.
It was delight for Pompey’s youngsters, who now entertain the Toon Army in a third-round fixture to be finalised.
The first goal-scoring opportunity of the evening arrived in the 13th minute when a slick passing move presented Mayes with the chance, which was tipped over the bar.
On 22 minutes, skipper Theo Widdrington strode forward and crashed a fierce right-foot effort which was taken well by Jake Maddock in goal.
Next Tommy Scutt steered a header at the far post back across goal, but Jez Bedford’s snapshot lacked power and dealt with easily at the near post.
It was Nick Hall at the other end of the pitch who pulled off the save of the night so far when, on 36 minutes, he parried a ferocious left-foot shot from distance delivered by Jamie Autorino.
With half-time approaching, Dan Smith whipped in a dangerous ball from the right which bounced just before the lunge of Mayes, ensuring he couldn’t make a connection from close range.
It was goalless at half-time, with neither side showing enough to deserve the lead.
Upon their return after the interval, Kyle McDowell’s cross from the left caused problems and met with a terrific striker from Scutt, but the keeper was equal to it.
There was a real scare for the hosts on 66 minutes when Autorino’s wickedly in-swinging corner was clawed out by Hall, but Ben Marett put the ball over from close range.
The game was in desperate need of a goal and Sam Woodward should have done better when Dan Smith’s deep cross from the right picked him out unmarked.
However, the Pompey player sent a first-time right-foot shot well wide of the far post.
The deadlock was finally broken on 80 minutes when Mayes headed home McDowell’s cross at the far post.
It was left to Scutt to wrap up matters in stoppage time with a far-post finish.
Pompey: Hall, Smith, Wakley, Widdrington, McDowell (Hancott, 89), Read, Scutt, Bedford, Woodward (Brooks, 82), Bradbury, Mayes (Lethbridge, 90). Subs Not Used; Collins, Casey.