Granted, the Fratton Park encounter could have ended in defeat, Pompey requiring to fight back from behind.
Nonetheless, the 1-1 draw still represented a disappointing outcome for the hosts against a side below them in the league.
Curiously, it also made it one win in eight Tuesday night matches this season, signifying something of a jinx for the Blues boss.
Not that an inability to beat the Robins should be excused, this was no hard luck story.
Reeco Hackett levelled Lewis Freestone’s sixth-minute goal in rather fortuitous manner to ensure the sides entered the interval at 1-1.
Yet while Cowley’s men lifted themselves for the second period, they didn’t carve out sufficient chances to claim victory.
In fact, considering large portions of the second half were spent in the Robins’ side of the pitch, the absence of further Pompey goals was hugely irritating.
The impressive Sean Raggett had a header saved, John Marquis saw a decent shot stopped, Ronan Curtis crashed one over, and there were other close opportunities.
But not nearly enough was offered in attacking terms to break down a stubborn Cheltenham, who, to be truthful, were largely comfortable at the back.
That disappointment prompted a few boos among the Fratton faithful at the final whistle, with such frustration understandable.
Still, Cowley can point to three games unbeaten since that Ipswich debacle which remains so raw, yielding five points.
Now Pompey head into a period of two cup fixtures as this stuttering season continues.
Louis Thompson was handed his maiden League One start for Pompey, following several encouraging substitute outings.
Previously the 26-year-old had started only in the Papa John’s Trophy for the Blues, for fixtures against AFC Wimbledon and Sutton United.
Yet he replaced Shaun Williams, who dropped to the bench having started 11 successive league fixtures.
In addition, Joe Morrell came in for the injured Ryan Tunnicliffe after being benched on Saturday as a precaution with a tight groin.
The midfield pair represented two changes to the Pompey side which defeated Bolton 1-0 for a second win in 14 matches in all competitions.
With Tunnicliffe missing from the match-day 18 with his leg problem, Gassan Ahadme was recalled to the bench after drifting away from the first-team frame in recent months.
Clark Robertson, Ellis Harrison, Paul Downing, Jayden Reid, Tunnicliffe and Liam Vincent were again all absent through injury.
Cheltenham kicked off proceedings and, on three minutes, Alfie May drove in a low right-footed shot which was comfortably collected by Gavin Bazunu.
Moments later, Ronan Curtis slipped in John Marquis down the left-hand side of the penalty area, but he declined to shoot and then slipped over, ending the move.
On six minutes the Blues found themselves behind through poor defending.
A looping throw-in from the right was accidentally deflected by Hackett into his own box and was picked up by Freestone.
With back to goal, the defender spun and fired a low shot past Bazunu to give Cheltenham a 1-0 lead.
On 13 minutes, Hackett’s free-kick from wide on the left was met with a stooping header by Marquis which ballooned over the bar, landing on the roof of the net.
Pompey just couldn’t get going, yet a superb right-wing cross from Marcus Harness just eluded Marquis and forced a Cheltenham defender to put it behind for a corner.
Moments later, the winger repeated the trick and this time an awful header from Hackett steered it wide when he should have done far better.
Thompson lifted the crowd on 30 minutes with a run from the halfway line culminating in a right-footed shot which Cheltenham’s keeper tipped over at his near post.
It was an encouraging moment in an otherwise drab half for the Blues so far as they chased the equaliser.
On 32 minutes Pompey had their equaliser, albeit in strange circumstances.
Harness combined with Romeo down the right and the latter’s cross was punched out by Scott Flinders only so far as Hackett.
From just inside the box, the winger side-footed a left-footed shot into the ground, with the ball ballooning into the air and into the net.
Hackett produced an almost apologetic goal celebration, nonetheless the Blues had drawn level at 1-1.
Cheltenham should have immediately regained the lead, only for the unmarked Kyle Vassell to chest the ball down and somehow volley wide from just six-yards out.
On the stroke of half-time, Curtis’ shot from 25-yards was spilled by Flinders, but he was able to gather without any Blues player capitalising.
When the second half got underway, Chris Hussey picked up the game’s first booking on 49 minutes following a late challenge on Harness.
Then Mattie Pollock had to receive treatment before replaced by Grant Horton in the 56th minute.
Pompey carved out an opportunity when Morrell showed lovely footwork to surge into the box before laying the ball off to Mahlon Romeo, whose cross to the far post was headed into the side netting by Curtis.
The hosts had started the second half encouragingly, producing much of the game’s play in the Robins’ half.
In the 65th minute, Hackett flashed a cross from the left which shot across goal. Maybe a touch over hit for one of his team-mates to make a connection with.
On 68 minutes, Ellis Chapman was replaced by Dan Crowley for the visitors, followed by Wiliams’ introduction for Thompson.
A clever ball from Harness slid in Marquis for a great scoring opportunity and although he struck the ball well, Flinders was equal to it with the save.
Miguel Azeez was introduced for only his second Pompey outing when he replaced Hackett on 75 minutes.
Pompey were finishing the stronger side and Flinders did well to beat out a Raggett header with a flying stop following a right-wing corner.
Marquis made way for George Hirst on 81 minutes, signifying the Blues’ final substitution.
With time running out, Curtis blazed a wonderful opportunity over the bar as Pompey failed to find the finishing touch to earn victory, with the game ending 1-1.
A message from the Editor, Mark Waldron
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