The doubts over Pompey’s promotion credentials multiplied following another dismal showing under the Fratton Park lights.
The Blues’ defensive selection has been increasingly unconvincing in recent weeks – and they were two goals down after just six minutes against Burton.
Granted, there was a comeback, Brett Pitman’s penalty securing a 2-2 draw with the penultimate kick of the League One encounter.
Yet the display raised many more questions than it answered as Kenny Jackett’s lacklustre side struggled to respond, despite possessing a numerical advantage for the final 66 minutes.
The half-time introduction of Gareth Evans finally injected energy – as did another substitute Andy Cannon – yet the performance was wholly unconvincing.
It was a fightback but hardly thrilling and not befitting a team supposedly meant to be surpassing last term’s fourth-placed finish.
Indeed, had it not been for Ryan Edwards barging over substitute Ellis Harrison after four minutes of time added on, it would have been another defeat to rival Coventry in the discontent generated.
As it was, the recalled Pitman stepped up to level – but the boos from the home support at the final whistle told their own tale.
Joe Sbarra’s opener and Kieran Wallace’s deflected shot from condemned Jackett’s men to a nightmare start – then the visitors had John-Joe O’Toole dismissed for two bookable offences.
Not that it could stir Pompey into action, as they limped in at half-time 2-1 down after Ronan Curtis reduced the deficit.
A patient Fratton faithful had to wait until time added on for the equaliser – and a point was saved.
Pompey had got themselves out of jail and the team selection for Saturday’s trip to Wycombe is anyone’s guess as this fitful start to the campaign drags worryingly on.
It had been 18 days since the Blues’ last League One outing – a 1-1 draw at Blackpool – with two cup matches in between.
For the visit of Burton, there were two changes to that Bloomfield Road starting line-up, with Pitman and Ryan Williams introduced.
Marcus Harness’ thigh injury, which Jackett claims will also deny his presence in next week’s south-coast derby, opened up a spot on the right flank.
That was handed to Williams, marking a full debut in his second Pompey spell, following a 19-minute comeback cameo against Norwich City under-21s.
Meanwhile, the recalling of Pitman was warmly received by the Fratton faithful before kick-off, the striker replacing Cannon in the number-10 role.
It represented the former Pompey captain’s maiden start of a campaign which saw him named on the bench for all nine previous fixtures in all competitions.
Elsewhere, Craig MacGillivray, Ross McCrorie and Curtis all came straight back into the team following international duty.
Meanwhile, Christian Burgess remained at right-back, with his rival and likely successor, fit-again James Bolton, on the bench.
The substitutes also included Evans, back following concussion and then a dead leg, and Oli Hawkins, who returned to the squad in the 3-1 win over the Canaries in the Leasing.com Trophy.
It took just three minutes for the visitors to take the lead and stun Fratton Park.
Lucas Akins cut in from the right, shadowed by Tom Naylor, and he pushed it out wide to Wallace, whose cross was initially blocked by Williams.
But it fell to Sbarra, who struck a first-time left-footed shot into the far corner.
Pompey found themselves 2-0 down after six minutes when a wicked deflection wrong-footed MacGillivray.
Wallace was allowed time and space to fire in an effort from 30 yards, which struck Paul Downing and found its way into the bottom corner.
It was a calamitous start from the hosts, yet the Fratton faithful refused to turn, doing their best to lift their wilting side.
There was a flashpoint on 20 minutes when the strong-running John Marquis lifted the ball through and was cynically blocked by O’Toole.
After consulting his linesman, the referee opted for a yellow card as punishment – a reasonable outcome considering a Burton team-mate was covering.
From the resulting free-kick, play eventually found its way to McCrorie down the left and his deep cross was met with a powerful diving header from Naylor which flashed wide.
Then, on 24 minutes, centre-back O’Toole did see red after hauling down Marquis.
Play was allowed to continue, with Pitman crashing a right-footed shot against the bar.
But referee Craig Hicks then returned to hand O’Toole a second booking and the visitors were rightly reduced to 10 men.
Pompey had their opportunity and Burgess produced a testing cross from the right which found the head of Curtis, whose header was caught by the keeper.
The deficit was reduced on 39 minutes following another encouraging cross from Burgess.
His delivery took a deflection on the way into the six-yard box and, when Marquis’ header was saved, Curtis pounced to lash a left-footed shot high into the roof of the net.
At the interval, Jackett introduced Evans for Williams – the Blues switching to three at the back with Curtis pushed up alongside Marquis.
That meant Evans playing right wing-back and Burgess moving inside as one of the three centre-halves.
The substitute quickly got into the action and on 50 minutes flighted in a cross which was met with a Curtis header but Kieran O’Hara tipped the ball over the bar.
Then Burgess’ deep cross was headed back at the far post by Curtis and Ben Close had a shot superbly charged down by Richard Nartay.
A thunderous challenge by substitute Colin Daniel on Marquis saw the defender come off worse with what appeared to be a cut head.
But he was quickly bandaged up and returned to the field.
It then took a stunning save from O’Hara to deny Curtis’ header from Haunstrup’s left-wing cross – the keeper somehow finger-tipping it around the post.
There were appeals for a penalty on 84 minutes when substitute Cannon skipped past Akins inside the box and tumbled to the floor but nothing was given.
A clever ball from Close then gave Marquis a glorious sight of goal but the striker dragged his shot wide with only the keeper to beat.
Then, four minutes into time added on, Harrison was nudged by Edwards with the ball high in the box and Pitman converted the penalty.
It finished 2-2, a point rescued, but the display which drew boos at the final whistle was far from convincing.