It appeared the Blues were heading for a rare point on their travels when Andre Dozzell netted in the 80th minute to cancel out Mihailo Ivanovic’s opener.
However, with two minutes of normal time remaining, Ivanovic headed home Casper De Norre’s precise cross from the right for his second and Millwall’s winner.
It was more frustration for John Mousinho’s men who lost in similar circumstances at Preston in their previous away match. And here are our Pompey player ratings...
9. Terry Devlin - 8
(Replaced by Thomas Waddingham on 89 mins) Chosen ahead of Aouchiche for the number 10 role, where his work-rate and physicality was hugely impressive. Collected a 29th-minute booking but that didn’t slow him down with a high-octane display. Photo: Jason Brown
10. Josh Murphy - 6
A couple of decent charges down the left wing, but otherwise didn’t see much of him as an attacking force as the Blues struggled to get him involved. Disappointingly anonymous. Photo: Matt McNulty/Getty Images
11. Colby Bishop - 7
Put in such a shift, including chasing back into the right-back area in time added-on to block a cross which resulted in a corner. Physically put himself about and his first-half shot brought a save from Jensen. Photo: Jason Brown
12. Portsmouth midfielder Josh Murphy (23) during the EFL Sky Bet Championship match between Millwall and Portsmouth at The Den, London, England on 5 April 2025.
Josh Murphy in action against Millwall. Picture: Jason Brown/ProSportsImages Photo: Jason Brown