In a match when neither keeper had much to do, particularly the visitors, Romain Esse’s 13th-minute goal was enough to earn Millwall victory.
Pompey raised their game in the second half, with Sammy Silvera and Zak Swanson catching the eye, yet they couldn't carve out enough opportunities to force home an equaliser.
And here are our Pompey player ratings...
5. Connor Ogilvie - 7
Not possible to rest him with Jacob Farrell’s injury so retained his place. Had some testing moments at Leeds, but was back to his usual dependable self and defensively rock solid throughout. Photo: Jason Brown
6. Ben Stevenson - 7
Took responsibility for set-pieces - including corners from both sides - and produced some very good ones. Always quietly effective for the Blues, everything is a minimum of fuss and very consistent. Photo: Jason Brown
7. Terry Devlin - 6
The versatile performer was asked to partner Stevenson as the holding midfielders and his energy and drive looked a little wasted. Header from Stevenson corner agonisingly went close early in the second half. Switched to right-back mid-way through second half. Photo: Jason Brown
8. Tom Lowery - 7
(Replaced by Elias Sorensen 66 mins) Played as the central midfielder furthest forward and buzzed around attempting to make things happen, always attempting to play positively. However, went down injured in the second half and was forced off, which is a real worry for Pompey. Photo: Jason Brown