Pompey will break a club record if they collect at least a point at Stevenage on Saturday (3pm kick-off).
It would stretch their unbeaten league run to 16 matches – something that has not been achieved since joining the Football League in 1920.
But their opponents have adapted quickly to life at this level since securing promotion as runners-up of the fourth tier last term.
That came after Steve Evans had been appointed manager towards the end of the previous campaign and steered a struggling side away from danger.
Boro began this season with three successive league wins and also knocked Championship side Watford out of the Carabao Cup.
Their excellent opening came to an end last weekend, however, with a 2-0 reverse at Reading after being reduced to 10 men midway through the first half.
Blues boss John Mousinho will have fond memories of the time he spent at Broadhall Way as a player between 2010 and 2012.
He netted the winning goal at Old Trafford as the club beat Torquay in the League Two play-off final, finishing as the club’s joint top scorer.
Injuries restricted his appearances in the following season, but he helped Boro finish inside the top six.
The two sides have not met in the league since Pompey’s triumphant 2016/17 campaign, although it was Stevenage who won both contests.
A clash in the EFL Trophy last term saw the Blues emerge as 3-0 victors, however, courtesy of goals from Jay Mingi, Josh Koroma and Joe Pigott.
Josh Dockerill (knee), Tom Lowery (knee) and Kusini Yengi (ankle) are the only players missing for Pompey.
Stevenage have a number of injury concerns, with Harry Anderson, Luther James-Wildin, Kane Smith, Dan Sweeney and Terence Vancooten all sidelined.
Nathan Thompson will also miss out after being sent off at Reading last week, but his brother Louis and fellow former Blues players Dan Butler and Ben Thompson could feature.
HEAD TO HEAD
Pompey: 5 wins
Stevenage: 5 wins
On The Road
Pompey: 3 wins
Stevenage: 4 wins
Pompey have sold their full allocation for the game, so please do not travel if you do not have a ticket.
Click here for a guide to visiting Broadhall Way that has been produced by the home club.
Referee: Simon Mather
Assistants: Damith Bandara and Scott Williams
Fourth Official: Stephen Finch
Overseas subscribers and match pass holders can watch all the action live, with accompanying commentary.
There will be post-match reaction on the website and our official YouTube channel, with highlights to follow on Sunday.
ALSO IN LEAGUE ONE
All games kick-off at 3pm
Bristol Rovers v Wycombe
Burton v Bolton
Cheltenham v Northampton
Exeter v Reading
Fleetwood v Shrewsbury
Leyton Orient v Cambridge
Lincoln v Blackpool
Oxford v Charlton
Peterborough v Derby
Port Vale v Carlisle
Wigan v Barnsley