Harvey Bradbury scored but Pompey reserves were beaten 3-1 by hosts Everton under-23s in the Premier League Cup.
Ian Foster’s Pompey side conceded once in the first half at Southport.
Dominic Calvert-Lewin struck the opening goal after 15 minutes.
An own goal from Tom Davies doubled Everton’s advantage after the break.
Calum Dyson then struck the third to seal victory for the hosts.
Bradbury pulled one back as he netted the final goal of the game.
Pompey starting XI: O’Brien, Oxlade-Chamberlain, Calvin Davies, Tom Davies, Haunstrup, May, Close, Lalkovic, Bedford, Naismith, Chaplin.