Nicke Kabamba was on target as Pompey Reserves beat Sheffield United to reach the quarter-finals of the Premier League Cup.
The striker bagged the only goal of the game late on at Westleigh Park, as the Blues continued their impressive run in the competition.
They started on the front foot and forced a couple of early corners that ultimately came to nothing.
Calvin Davies also whipped in some dangerous deliveries, one of which cannoned off an opposition defender and flew narrowly over the bar.
Another cross from the right-back then just evaded the onrushing Kabamba, as the Blues continued to probe away without being able to find an end product.
There was not much to note at the other end of the pitch and a shot from Horatio Hurst flew wildly past Liam O’Brien’s post.
Brandon Haunstrup then picked out Kabamba in the box and the strike drew the first save of the game from Josh Perryman.
The Blades keeper then comfortably denied Conor Chaplin following some good build-up play involving Haunstrup, Jamal Lowe and skipper Adam May.
Half Time: Pompey 0 Sheffield United 0
O’Brien was finally called into action early in the second half, denying Harvey Gilmour following good work from Jake Wright.
But the Blues were soon on the attack themselves and Perryman dived bravely at the feet of Kabamba.
The keeper then denied Lowe with his feet before the follow-up effort from Chaplin was deflected over.
It was an open tie as both sides sensed an opportunity to reach the last eight, with chances starting to flow at both ends.
A teasing cross from Haunstrup was hacked behind by the Blades, with Kabamba and Chaplin both hovering.
And Pompey finally broke the deadlock with 10 minutes remaining, as Perryman spilled Lowe’s shot and KABAMBA followed-up to convert the loose ball.
The striker should have had another late on, but appeared to trip over the ball after being teed-up by Chapin.
It did not prove costly, though, as the hosts saw out the final few seconds to secure safe passage to the next round.
Pompey: O’Brien; C.Davies, Talbot, Widdrington, Haunstrup; Linganzi, May (c); Oxlade-Chamberlain (Bedford 60), Chaplin, Lowe; Kabamba
Subs not used: Bass, Wakley, Woodward, Bradbury
Sheffield United: Perryman, Bennett, Kelly, Cantrill, Charlesworth, Harrington, Slater, T.Smith, Gilmour, Hirst (K.Smith 76), Wright
Subs not used: Warhurst, Ford, Ferguson, Greaves
Referee: Anthony Coggins