Pompey’s Hampshire Cup run came to an end as they let slip a two-goal lead to lose a quarter-final tie at Bournemouth.
They appeared to be cruising into the last four following early goals from Tom Lowery and Koby Mottoh.
But a hat-trick from David Brooks and Daniel Adu-Adjei’s brace saw the home side hit back to stun the Blues.
There were plenty of first team players involved for Pompey, with John Mousinho opting to give minutes to those in need of time on the pitch.
The trio of Clark Robertson, Jay Mingi and Lowery were all included as they continue to make the step up to full match fitness following long spells out injured.
Michael Jacobs, Joe Pigott, Denver Hume and Josh Oluwayemi were the other members of the senior squad named.
They joined the academy quartet of Brian Quarm, Josh Dockerill, Adam Payce and Mottoh, with several more under-18s on the bench.
Bournemouth handed a start to Brooks, as the Wales international made his first start since being given the all clear from cancer.
When the action started, he played an excellent pass across to Ben Winterburn, who lifted the ball over Oluwayemi, only for the keeper to collect it before the ball could cross the line.
Skipper Ben Greenwood then capitalised on a poor touch and drilled a low shot narrowly past the post.
But it was the Blues who broke the deadlock on 13 minutes after Billy Terrell had tried to play a shot pass to Toure Williams.
LOWERY nipped in to steal it before rounding the keeper and rolling the ball into the bottom corner.
And the visitors capitalised on another error to double the advantage midway through the first half, with Lowery crossing for MOTTOH to convert from close range.
Pompey were looking comfortable, only for some extremely sloppy play to allow the Cherries to score four times in the space of just 12 minutes.
They won possession and although Oluwayemi got something on the shot from Brooks and Dockerill got back to clear off the line, the ball ricocheted back off the midfielder and into the net.
Adu-Adjei then found Brooks on the right and raced half the length of the pitch to collect the return pass and fire home off the inside of the post.
The stunned Blues almost immediately fell behind, although the effort from Brooks took a big deflection off Hume to beat Oluwayemi.
And Brooks then completed his treble, slotting the ball home after Pompey had again lost possession in their own half.
Pompey finished the half with an attacking flourish and both Robertson and Payce saw efforts blocked.
Half Time: Bournemouth 4 Pompey 2
Jacobs made way for Harvey Laidlaw at the break, while Quarm collected an injury straight after the restart and was replaced by Jack Fox.
Pompey were passing the ball around nicely in their search for a route back into the tie, but struggling to find a way through the hosts’ back-line.
There were a couple of free-kicks from Pigott, but one was comfortably gathered by Terrell and the other did not quite have enough dip.
And Bournemouth extended their lead against the run of play on 65 minutes, as Adu-Adjei raced through and calmly slotted home.
Skipper Robertson’s evening was complete and he was replaced by teenager Dan Murray, while Lowery then made way for Mitch Aston.
Adu-Adjei might have had a hat-trick of his own, but Oluwayemi came to the rescue with a smart save.
It was, by this point, a very young Blues side and despite fighting until the end, they were unable to find another goal.
Bournemouth (4-3-3): Terrell; Genesini, Kinsey-Wellings, Greenwood (c), Boutin (Gidaree 76); Brown (Rees-Dottin 87), Williams, Winterburn; Brooks (Dacosta Gonzalez 46), Adu-Adjei, Johnson (Morgan 53)
Goals: Brooks 25, 33, 37, Adu-Adjei 30, 65
Sub not used: Crisp
Pompey (4-3-3): Oluwayemi; Quarm (Fox 47), Dockerill, Robertson (c) (Murray 66), Hume; Mingi, Lowery (Aston 71), Payce; Mottoh, Pigott, Jacobs (Laidlaw 46)
Goals: Lowery 13, Mottoh 22
Sub not used: Steward
Referee: Gary Parsons