Danny Cowley used the fixture against League Two opposition to give his fringe players an opportunity to impress - a chance they failed to take.
After a goalless opening 45 minutes, the Us created the most chances in the second half and left Pompey answerless after netting twice in front of the Milton End.
The defeat leaves the Blues on the cusp of elimination from the EFL Trophy and provides more questions than answers for Cowley.
An opportunity missed
Pompey boss Danny Cowley made eighth changes from the rout over Sunderland last night as he handed much needed minutes to those lacking in league appearances.
Players such as Michael Jacobs, Gassan Ahadme, Paul Downing and George Hirst, were all brought in from the cold to face the Us at Fratton Park.
However, those on the field did less than impress and little to change their manager’s mind about their current on-field situation.
Ahadme was replaced shortly after the half-time interval, as he failed to replicate his Bournemouth double from last week’s friendly with the Cherries.
The 20-year-old once again followed a worrying trend that was apparent in matches against AFC Wimbledon and Basingstoke Town as he didn’t deliver where it truly mattered.
Similarly, Jacobs flattered to deceive throughout and grew in anonymity as the match progressed. It was clear to see he was suffering from ring rust as he couldn’t make a serious impact when on the ball, but a player who has proved his worth for Pompey in the past should be able to show glimpses of such form against lower league opposition.
Question marks have already been raised about the Blues’ strength in depth and the performance from certain individuals against Sutton did little to thwart those thoughts.
More harm than good?
There was always a worry when Cowley fielded an experienced side at Fratton Park that injuries could come back and bite the squad.
Unfortunately, for the former Huddersfield Town boss he saw three players forced off at Fratton Park.
On the stroke of half-time Paul Downing had to receive treatment after pulling up despite the lack of presence from any Sutton player. It was later revealed that he had to leave the field of play due to a hamstring injury, with the 28-year-old being sent for a scan.
This will be another set-back for the centre-back who has patiently waited for a chance in the first team after watching the Blues’ last four league fixtures from the bench. The club will learn the extent of his injury when the results from the scan return.
Potentially joining Downing on the treatment table is Ellis Harrison. Not long after entering the field from the bench he was required to leave it after feeling the full force of challenge from a Sutton defender.
At face value the incident looked no more than a hard challenge, but at second glance the Us defender may have been lucky to stay on the pitch. To the 27-year old’s credit, he looked to shake it off on the touchline but it was apparent he could no longer continue.
Throw in a dead leg as Haji Mnoga was forced off at the break and it proved a costly night for the squad.
First full 90 for Louis Thompson
Perhaps the only positive to come from their Sutton humbling was the fact that Louis Thompson completed his first full 90 minutes in royal blue.
The 26-year-old arrived on a free transfer from Norwich in the summer but was already carrying an injury which limited his early Blues progress.
And as a result, last night’s defeat to the Us was only his second start for the club as he’s yet to make a League One starting XI.
Thompson was arguably Pompey’s best player on the night and showed glimpses of quality that can only encourage Cowley. Like he did in the club’s last fixture in the competition, he occupied a slightly deeper midfield role which allowed him to not only protect the back line, but retrieve the ball and look to forge Blues counter attacks.
It’s also worth mentioning that the midfielder was one of a few players to register a shot against Sutton when he collected the ball on the edge of the box before seeing his speculative effort blocked.
The former Swindon loanee is potentially the only Pompey player to have left Fratton Park with a grain of credibility and by staying fit after playing a match’s entirety, offers a small chink of light after a dark night.