Jamal Lowe celebrated his miraculous recovery from injury with a goal that ensured Pompey began the new season with victory over Luton.
He slotted home in the first half to cap an enjoyable afternoon at a Fratton Park that was bathed in south coast sunshine.
But the Blues had to withstand some heavy pressure at times, with the Hatters twice hitting the woodwork in their quest for an equaliser.
Kenny Jackett handed debuts to four of his summer signings, with Craig MacGillivray, Lee Brown, Tom Naylor and Ronan Curtis all starting.
But the big surprise when the teams were announced was the inclusion of Lowe, who was expected to miss out after injuring his ankle against Utrecht the previous week.
There was also a start for Brandon Haunstrup on the left of midfield, as Jackett opted to stick with the 4-4-2 system he had preferred towards the end of pre-season.
The visitors received an early scare as skipper Alan Sheehan crashed into the advertising hoardings and ended up in the Milton End moat.
It was nervy few moments as the crowd waited for the centre-back to emerge, but thankfully he was unscathed.
Luton – who were promoted from League Two last term – started the brighter side and when Sheehan’s delivery was flicked on by Harry Cornick, the ball flashed dangerously across the face of goal.
A moment of controversy followed as Curtis rose for a challenge and there were suggestions of an elbow being used as he crashed to the turf.
The Fratton faithful certainly appealed for a red card, but after consulting with his assistant, referee Gavin Ward decided to take no action.
Pompey’s fans did have cause to cheer on 16 minutes, however, as their side managed to break the deadlock.
It was LOWE who grabbed the first goal of the season, slotting in from inside the box after Curtis had done well to get to the byline and cut the ball back.
Most of the game’s clearest chances were still falling Luton’s way, though, and Nathan Thompson had to intervene when Jorge Grant tried to pick out James Collins in the box.
They then had two excellent opportunities to draw level within the space of a few minutes – and on both occasions some visiting fans thought they had.
First up was Pelly-Ruddock Mpanzu, whose low effort from the edge of the box could not quite creep into the bottom corner.
Then, after Brown had been booked for a foul on James Justin, Sheehan’s free-kick cannoned back off the upright.
But the closing stages of the half passed by relatively incident free, although former Fratton loanee Dan Potts did receive a booking for a foul on Lowe.
Half Time: Pompey 1 Luton 0
Brett Pitman did not emerge from the tunnel for the start of the second half, with Oli Hawkins taking his place up front and Naylor claiming the captain's armband.
But it was fellow striker Curtis who forced Marek Stech into action with a curling shot on 50 minutes, although the flag had been raised for offside.
The Blues were looking a threat on the counter-attack and when Curtis surged towards goal, Alan McCormack decided to take one for the team.
Luton’s midfielder deliberately clipped the heels of his opponent and there was no surprise when he received a yellow card.
But the Hatters were looking dangerous themselves and when the hosts lost possession, Collins smashed a shot against the woodwork.
MacGillivray then came to the rescue just past the hour mark, doing well to deny Cornick from close range.
Pompey made their second change in between those chances, with Anton Walkes making way for Ben Close in the centre of the pitch.
Thompson’s shot flew off target, as the hosts tried to ease the pressure and injured himself in the process.
It forced Jackett into his final change of the afternoon, with Christian Burgess taking up an unfamiliar right-back role.
Fellow defender Jack Whatmough was looking assured and halted one Hatters attack with a couple of key tackles in quick succession.
There was also persistence from Naylor to win the ball back after losing possession, while MacGillivray did well to cut out Mpanzu’s low centre.
Nerves started to creep in as the seconds ticked down and only rose when Whatmough conceded a free-kick just outside the box.
It was Sheehan who stepped up to curl a shot around the wall, but MacGillivray dived to his right to push the ball clear.
Former Blues players Jake Jervis and Sonny Bradley both came on and were thrown up front for the closing stages, but Luton were unable to find a late leveller.
Pompey (4-4-2): MacGillivray; Thompson (Burgess 71), Whatmough, Clarke, Brown; Lowe, Naylor, Walkes (Close 60), Haunstrup; Pitman (c) (Hawkins 46), Curtis
Goals: Lowe 16
Booked: Brown, Curtis
Subs not used: McGee, Donohue, Evans, Chaplin
Luton (4-1-2-1-2): Stech; Justin (Bradley 90+1), Pearson, Sheehan (c), Potts; McCormack (Jervis 87); Mpanzu, Grant; Lee; Cornick (Shinnie 78), Collins
Booked: Potts, McCormack, Justin, Sheehan
Subs not used: Shea, Rea, Stacey, Gambin
Referee: Gavin Ward
Attendance: 19,018 (2,392 away fans)