There were no changes for either side at the break, although City were forced into one soon after the restart when Tendayi Darikwa went down following an innocuous-looking challenge. He received lengthy treatment on his knee and initially returned to his feet, but was unable to continue.
City were briefly reduced to ten men while the change was prepared, with Andrei Coubis eventually introduced for his home debut. Shortly afterwards, Rocco Shein was booked for pulling back Ben House as the striker looked to break away, and the resulting deep free kick was flicked on by Coubis but just evaded House before Portsmouth cleared.
The visitors made a double change after 57 minutes, with Ebou Adams and Josh Murphy replacing Shein and Ryan Kavuma-McQueen, and they began to offer more of a threat. George Wickens saved from Colby Bishop at a tight angle before City fashioned a half-chance of their own, Reeco Hackett curling a delivery into the area which House flicked goalwards without seriously troubling Nicolas Schmid.
City made two further changes after 66 minutes as Tom Bayliss replaced Ivan Varfolomeev and Rob Street came on for Dom Jefferies. Adam Reach was then booked after Abu Kamara got the better of him, forcing the City defender to tug him back.
Portsmouth restored their two-goal advantage after 69 minutes, with City contributing heavily to their own downfall. Coubis gave possession away to Adams, who needed no second invitation and produced an excellent strike from distance to beat Wickens and make it 3-1.
Tom Hamer was booked soon afterwards for a foul on Bishop before City made another attacking double change, Tanto Olaofe and Mason Melia replacing House and Freddie Draper with 15 minutes remaining.
Portsmouth withdrew Murphy for Marko Milovanovic shortly afterwards, but City continued to search for a route back into the contest. Street fired a dangerous ball across the face of goal after 85 minutes, with Olaofe inches away from applying the finishing touch.
The visitors immediately broke at the other end and Adrian Segecic should have added a fourth, but his effort was straight at Wickens. Portsmouth then made two late changes, with Marlon Pack and Kamara replaced by Josh Knight and Luke Brooke-Smith.
Late on, City almost added a second; a long ball fell to Street, and despite a miss-hit, it took a diving header to put it out for a corner. Sadly, the corner was easily held by Schmid. Street had another chance with four minutes of injury time played, Bayliss’s ball from a free kick headed across goal and wide.
There was no way back for City after that as Portsmouth saw out a 3-1 victory in front of 10,545 supporters, including 1,178 travelling fans.
Surely must get the new guys involved ASAP and get the Danish striker signed up quickly.