Joe Gallen hailed the professionalism of his senior players following a third successive pre-season victory for Pompey.
There were plenty of youngsters on display in a 2-1 win for the Blues against non-league Bognor at Nyewood Lane.
And it was one of them who opened the scoring, with Eoin Teggart firing home before skipper Brett Pitman doubled the advantage.
Several more academy players entered the fray during the second half and Bognor made the most of that, with former Fratton forward Dan Smith reducing their deficit.
The Rocks fought hard in their attempts to secure a share of the spoils and Gallen admitted that his troops were hanging on at times.
Pompey’s assistant manager said: “Our side got younger and they scored an early goal in the second half, which saw our confidence drop a little bit.
"All of the senior players showed a fantastic attitude to help the younger lads."
“But everyone kept going and we just about got ourselves over the line after losing our way for a little bit.
“Bognor looked like they might get a second and I thought Alex Bass made an excellent save, while Matt Casey and Christian Burgess were brilliant.
“But, having said that, we hit the bar three times in the first half and it could have been done and dusted.
“Brett was a bit unlucky because he struck the woodwork twice, but he got his goal and showed what a great finisher he is.
“All of the senior players showed a fantastic attitude to help the younger lads, who had a good experience.
“That’s exactly what we asked of them and I’ve seen at other clubs that it doesn’t always happen like that.”