Pompey failed to find a way back against 10-men as Southampton won the south-coast derby.
The Saints took a 20th-minute lead through James Bree, only to have Cameron Bragg sent off on the stroke of half-time for two bookable offences.
That left the Blues with roughly 45 minutes to find a leveller against the numerically disadvantaged hosts, but they barely threatened, despite plenty of promising moments.
In the end Southampton comfortably retained their lead and claimed a 1-0 victory - and here are our Pompey player ratings…
1. Portsmouth winger Keshi Anderson (21) during the EFL Championship match between Southampton and Portsmouth at Saint Marys Stadium, Southampton , England on 11th October 2026
Pompey fall to a 1-0 defeat at Southampton. Picture: Jason Brown | Jason Brown
2. Nicolas Schmid - 8 - Man of the Match
Inspired recall to the side in place of Daniel Bielica after a four-game absence. Produced a huge early save with his left foot to deny Larin and after the break brilliantly thwarted Scienza. Those saves at least kept Pompey in it to dream of a comeback. | Portsmouth Football Club/Jason Brown No further distribution permitted without prior written permission/agreement
3. Zak Swanson - 7
(Replaced by Keshi Anderson on 77 minutes) Started off at right-back and later became left-back to again demonstrate his versatility. Always a ferocious competitor who rises to big occasions and produced some excellent interceptions, particularly in the first half. | Jason Brown
4. Madiodio Dia - 6
Maintained his run in the side and it was another mixed afternoon. Can be hugely erratic, which leaves him open to criticism. Still, had some good moments and can be strong defensively. | Jason Brown