John Mousinho’s men trailed 3-0 at the interval and never looked like finding a way back into the match, despite a system switch and using three substitutes.
Orient were comfortably the superior side and that is now five points from six matches – and here are our Pompey player ratings...
9. Abu Kamara - 3
Very quiet first half and it didn’t improve after the break. Great chance when Lowery put him through but shot was blocked by defender’s challenge. Switched to wing-back, both right and left, at 3-0 down, but game passed him by and failed to make any impact. Photo: Jason Brown
10. Colby Bishop - 4
At 2-0 had the chance to reduce the deficit from the penalty shot, but awful spot kick was comfortably saved. Really struggling for form at the moment and it’s a worry. Photo: Bryn Lennon
11. Paddy Lane - 4
(Replaced on 77 mins by Josh Martin). Had some promising moments in the first half, but crossing let him down. Switched to left wing-back in second half and well-handed by Galbraith before switched sides to right wing-back for a third role. Disappointing. Photo: Jason Brown
12. Portsmouth midfielder Marlon Pack (7) battles with Leyton Orient midfielder Max Sanders (23) during the EFL Sky Bet League 1 match between Portsmouth and Leyton Orient at Fratton Park, Portsmouth, England on 13 January 2024.
Marlon Pack in the thick of the action against Leyton Orient. Picture: Jason Brown/ProSportsImages Photo: Jason Brown