Pompey were beaten by Championship opponents Coventry in their only Fratton friendly of the summer.
Viktor Gyökeres and Joe Panzo both found the target after the break, while City keeper Simon Moore made a string of fine saves at the other end.
Former Blues loanee Tyler Walker had a chance to score on his south coast return, only to see a late penalty saved by Josh Griffiths.
Those fans seated inside the redeveloped South Stand and North Lower got their first glimpses of several new signings.
Joe Pigott led the line, while there were also starts for Marlon Pack, Joe Rafferty and Griffiths, as Danny Cowley stuck with the same side that beat Leyton Orient earlier in the week.
Pompey came close to taking an early lead after Michael Jacobs and Connor Ogilvie combined well on the left.
The latter flashed a low delivery across the face of goal, but the ball was agonisingly out of reach for both Pigott and Reeco Hackett.
There were not an abundance of chances, although Callum O’Hare and Gyökeres had shots blocked in quick succession from inside the area.
Matty Godden then escaped down the right and slid a pass towards Jake Bidwell at the far post, with Joe Rafferty having to clear from the line.
Pompey were trying to force their way through the Sky Blues back-line, who were remaining resolute.
And when Rafferty swung a deep cross into the box from the right, Ben Wilson got there just before Pigott to punch clear.
Half Time: Pompey 0 Coventry 0
Michael Jacobs was withdrawn at the break, with Colby Bishop brought on for his first Pompey appearance.
But it was Coventry who broke the deadlock on 54 minutes after the hosts had gifted them possession from a free-kick.
They advanced quickly up the pitch and Gyökeres rifled a low shot into the bottom corner of Griffiths’ net.
There was an immediate response, however, and Louis Thompson would have been celebrating an equaliser had Moore not got down to make a fine save.
Pompey were suddenly in charge and it took a couple more super stops from Moore to frustrate them.
The first prevented Bishop from turning home Ogilvie’s delivery, while the second came from a deflected Ronan Curtis effort.
Coventry hit back, though, and doubled their lead on 72 minutes, as Panzo arrived at the back stick to convert Bidwell’s cross.
And Walker had an excellent chance to wrap things up just moments after being brought on as a substitute.
The striker was brought down in the box by Haji Mnoga, but his penalty was saved by the leg of Griffiths.
Pompey (4-4-2): Griffiths; Rafferty (Swanson 77), Mnoga, Robertson (c), Ogilvie; Hackett (Tunnicliffe 60), Pack, Thompson (Mingi 77), Jacobs (Bishop 46); Pigott, Curtis
Subs not used: Oluwayemi, Freeman, Vincent, Jewitt-White, Bridgman, Gifford
Coventry (3-4-1-2): Wilson (Moore 46); Hyam (Rose 73), McFadzean (c), Panzo (Doyle 73); Dabo (Burroughs 73), Hamer (Sheaf 46), Allen (Eccles 46), Bidwell; O’Hare; Gyökeres (Walker 78), Godden (Tavares 78)
Goals: Gyökeres 54, Panzo 72
Sub not used: Billson
Referee: Charles Breakspear
Attendance: 5,694 (458 away fans)