Pompey’s numerical disadvantage was exposed in embarrassing fashion as Barnet knocked them out of the Carling Cup last night.
Lawrie Sanchez’s men only stayed in the Football League on the final day of last season.
But just two matches later they pulled off a 1-0 cup victory at Fratton Park.
What’s more, Barnet fully deserved it.
This was no fluke, no fortuitous result, no freak of football. It was 100 per cent the real deal.
It was not the same Blues team which twice fought back to claim a 2-2 draw at Middlesborugh a little over 72 hours earlier.
Cotterill was starved of options, which forced him to play a variety of players in unfamiliar positions for the occasion.
No Hermann Hreidarsson or Tal Ben Haim for the Pompey boss.
The pair were both on international duty, while Jason Pearce was again suspended.
And, just as crucial, there were still no new faces in the squad as Cotterill continues to wait for the sight of reinforcements.
At Fratton Park last night he was able to name just three substitutes out of a possible seven.
As for the League Two outfit, they named six.
A harsh reminder – if ever it was needed – for those occupying the directors’ box and those fans who bothered to turn up.
Fortunate then, that the crowd numbered just 4,464 – appallingly low due to ridiculous pricing of £17 for an adult ticket.
Still, those present booed Pompey off at the final whistle after witnessing an abject display.
It was arguably the poorest performance of Cotterill’s era to date as they received their just desserts.
Ultimately, Mark Hughes’ header from Mark Marshall’s 30th-minute cross settled matters.
Had Izale McLeod been able to finish two one-on-ones – and had it not been for impressive debut-making goalkeeper Stephen Henderson – then the scoreline would have been even greater.
As it was, Aaron Mokoena should have hit the target with a first-half effort, Dave Kitson had a header tipped over and Greg Halford saw his late header saved low down by Dean Brill.
And that was it from the Championship side.
Inevitably, Cotterill threw on both of his subs – Kanu and Ryan Williams – but even that couldn’t rescue matters.
It meant a first defeat at this stage since losing 2-1 at home to Colchester United under Graham Rix 10 years ago.
Liam Lawrence, who missed the draw with Middlesbrough on Saturday, had earlier declared himself fit and was immediately restored to the starting line-up, reclaiming the captaincy from David Norris.
That ensured Williams will wait a little longer for his first Pompey start.
Elsewhere, Henderson was given his debut in place of Jamie Ashdown, who dropped to the bench.
And with Ben Haim and Hreidarsson linking up with their national sides, there was also a first start for Christian Dailly.
The veteran was named in the centre of midfield, with Mokoena moving to right-back – a role he occupied in the friendly at the Hawks in pre-season.
Filling in for Hreidarsson at left-back was Joel Ward, who had served on the right-hand of midfield against Middlesbrough.
Meanwhile, Pompey were a staggering four players short of filling the bench.
Ashdown, Williams and Kanu were those named in the seven potential spots, Barnet having three more in their dugout.
The visitors kicked off but it was to be Pompey who had the first meaningful chance of the game.
On nine minutes, Lawrence swung in a beauty of a cross from the right which was met by Kitson at the far post.
But the former Reading and Stoke striker could only head it onto the roof of the net.
Barnet, however, should have taken the lead in the 15th minute through McLeod.
Once signed by Charlton Athletic for £1m, the striker was put clean through on goal but his touch was a little heavy and Henderson rushed off his line brilliantly, turning the ball away for a corner.
The Blues responded with two great chances inside a minute.
Firstly Mokoena wastefully headed over a free-kick delivered by Lawrence, then Hayden Mullins shot straight at Brill from close range following good work from Norris and Kitson.
Yet it was the Bees who took the lead on the half-hour mark after Henderson came for a corner and missed it.
Halford cleared but Mark Marshall was on hand to deliver the ball back inside the area when Hughes rose to plant a header home.
Moments later, McLeod broke down the right but again Henderson charged out to block.
Pompey were indebted to the assistant referee’s flag on 38 minutes, as he prevented the visitors going further ahead.
Marshall’s right-wing corner was headed home by defender Clovis Kamdjo, only to be ruled out for off-side.
Ward had a glorious opportunity to equalise on the stroke of half-time but volleyed another sublime cross from Lawrence well wide of the target.
For the second half, Dailly dropped to the left-back, with Ward switching flanks and Mokoena moving up into midfield.
Both full-backs had struggled throughout the first half against their respective wide men and the move was an attempt to shore up the defence.
However, at the other end of the pitch, the Blues continued to be bereft of ideas.
Brill was at least forced into a save in the 61st minute when he pushed Kitson’s looping header from Lawrence’s cross over the bar.
Halford then saw a header from Norris’ corner saved low down by Brill, with Kanu lurking.
And that was it.
Barnet continued to push forward but their victory was never in doubt.
It was an embarrassing defeat for the home side and yet another reminder of how urgent it is to strengthen their meagre squad.