Pompey’s young pretenders choked at their audition as Sutton United inflicted a first pre-season defeat.
Paul Cook opted to rotate his Blues squad for Saturday’s visit to the National League South champions.
The outcome was a 2-1 loss as Paul Doswell’s non-leaguers secured a deserved victory on their Gander Green Lane artificial playing surface.
Had it not been for the impressive arrival of the cavalry for the final 21 minutes, the scoreline would have been even more convincing.
As it was, Christian Oxlade-Chamberlain netted on 81 minutes during a late rally inspired by Cook’s nine substitutions.
However, the galvanising entrance of Carl Baker, Gary Roberts, Michael Doyle and Co could not secure a draw.
It ensured Pompey slipped to defeat in their fourth outing of the summer, following wins over Bohemians and the Hawks, in addition to a Sligo draw.
And for Cook, team selection options to mull over after many given the opportunity to shine flunked.
Alex Bass, Brandon Haunstrup, Ben Close, Adam May, Ben Tollitt and Adam Barton were among those in the starting XI, with the bulk of senior players on the bench.
Yet after only eight minutes the visitors found themselves behind, with former triallist Roarie Deacon netting.
Full-back Dan Spence was given time to deliver a cross from the right and the ball was laid into the path of Sutton’s new recruit for a well-placed finish.
Dan Wishart then produced a stunning run down the left before rattling in a shot from the angle which was beaten out at his near post by Bass.
The crossbar spared the Blues falling further behind on 32 minutes when Bedsente Gomis planted a free header from Deacon’s right-wing cross against the woodwork.
Barely 60 seconds later it was 2-0 when Burge’s right-wing corner was powerfully headed home at the far post by Gomis, with Pompey’s defence rooted.
There were no substitutions after the break and Craig Eastmond wasted a glorious opportunity two minutes following the restart, blazing over as he charged into the box after Deacon had pulled the ball back.
It took until the 57th minute for the Blues to initiate their best move of the match so far, with Ben Close put clean through.
The midfielder cut inside and took too long before being closed down, the ball falling to Curtis Main whose clever lob struck the crossbar.
On 69 minutes, Cook made nine changes, with only Bass and earlier substitute Whatmough remaining on the field of play.
Immediately the visitors were pepped up, Theo Widdrington’s shot blocked from close range, Baker firing a free-kick just wide and Roberts seeing a shot saved.
Pompey reduced the deficit on 81 minutes when Noel Hunt’s quickly-taken free-kick released Baker down the right and his low cross was turned in by Oxlade-Chamberlain.
It was nothing more than a consolation, though, as the visitors slipped to defeat.
POMPEY: Bass, Sessegnon (Talbot, 69 mins), Burgess (Whatmough, 63 mins), Barton (Widdrington, 69 mins), Haunstrup (Stevens, 69 mins), Close (Rose, 69 mins), May (Doyle, 69 mins), Tollitt (Baker, 69 mins), Chaplin (Oxlade-Chamberlain, 69 mins), Lalkovic (Roberts, 69 mins), Main (Hunt, 69 mins). Subs Not Used: Crowe, Bradbury.
SUTTON: Worner, Spence, Wishart (Amankwaah, 63 mins), Beckwith (John, 69 mins), Eastmond, Jamie Collins, Roarie Deacon, Bedsente Gomis (Bailey, 76 mins), Ryan Burge (Downer, 74 mins), Dan Fitchett (Dundas, 60 mins), Ross Stearn (Hudson-Odoi, 66 mins). Subs Not Used: Shaw, McAllister.