A stoppage-time goal saw Pompey Academy beaten 2-1 by Bournemouth at Copnor Road to relinquish top spot in the Youth Alliance League.
Daniel Adu-Adjei turned home a Baylin Johnson cross to give the Cherries the lead on the stroke of half-time.
But the hosts fought back and were level on the hour mark, when Dan Gifford (pictured) converted Adam Payce's delivery.
It looked like the spoils would be shared, only for Michael Dacosta Gonzalez to find the bottom corner right at the death.
Professional development phase coach Liam Daish said: “It was a really good game against a Bournemouth side who are always one of the strongest teams in our division.
“We held our own early on, defended strongly and it looked encouraging against powerful opponents.
“But we went behind just before the break after they were able to get down our left-hand side – we probably could have done better to pick the forward up.
“The response in the second half was positive, though. We showed a lot more belief in ourselves in possession and caused Bournemouth a few problems.
"There was so much good work from us, so it’s just a shame we couldn’t see it through to at least take something from the game."
“We pressed the ball as often as we could, making sure we remained in the game and created a number of chances.
“Adam then put the ball into a decent area and Dan was able to get between the two centre-halves and finish well.
“There was not much between the sides at that point, although there were times when our defence got a little stretched.
“But that wasn’t for long periods and you know there will be some difficult moments when you’re facing a side like Bournemouth.
“We should have defended their second goal a bit better. It shows that we have to be on it – especially against the better teams – from the first whistle to the last.
“There was so much good work from us, so it’s just a shame we couldn’t see it through to at least take something from the game.
“Overall, however, there were a lot of positives that we can build on as we prepare for the next match.”
Pompey: Steward, J.Fox, Kaba, Fish, Hughes, Howell (Longhurst 81), Simpson, C.Fox (Whitaker 66), Bridgman, Payce, Gifford