Pompey and Lincoln had both enjoyed bulldozing past whatever was put in front of them in recent weeks.
But the duo were stopped in their tracks at the weekend, with the Blues losing at home to Charlton and the Imps defeated at Doncaster.
So a return to winning ways will be the focus of Kenny Jackett and Michael Appleton when the pair clash at Sincil Bank this evening (7pm kick-off).
The latter had led his side to the top of the League One pile before that Keepmoat Stadium reverse dropped them to third position.
They are still four places – and five points – above Pompey, who will be looking to close that gap and climb back into the play-off spots.
City’s only loss on their own patch in the league came at the hands of Bristol Rovers last month, although they were also thrashed 7-2 by top-flight champions Liverpool in the Carabao Cup.
You have to go back 40 years to find the last time Lincoln came out on top in a meeting between the teams – although there have been just six encounters since.
Pompey won both contests last season, with Ronan Curtis and John Marquis on target in a 2-0 victory at Sincil Bank.
Jack Whatmough is set to be out for around three weeks with a hamstring problem, with Rasmus Nicolaisen likely to replace him in defence.
Michael Jacobs (knee) is still sidelined, but Ellis Harrison returned to the pitch against Charlton on Saturday.
Lincoln will be without the injured trio of Liam Bridcutt (thigh), Callum Morton (shoulder) and Joe Walsh (knee), while Max Melbourne (thigh) is also a doubt.
HEAD TO HEAD
Pompey: 10 wins
Lincoln: 5 wins
At Sincil Bank
Pompey: 4 wins
Lincoln: 3 wins
Referee: Carl Brook
Assistants: Christopher Ward and Kenwyn Hughes
Fourth Official: Gareth Mellor
Supporters in the UK can watch the action live – with graphics, commentary and replays – by purchasing a match pass for £10.
Please note that subscribers based in the UK and Ireland will still need to purchase a match pass in order to watch the game live.
ALSO IN LEAGUE ONE
Games kick-off at 7pm unless stated
Shrewsbury v Burton (6pm)
Blackpool v Wigan
Bristol Rovers v Peterborough
Charlton v Fleetwood
Crewe v Gillingham
Oxford v Rochdale
Plymouth v Swindon
Sunderland v Ipswich
AFC Wimbledon v Doncaster (7.45pm)
Northampton v MK Dons (7.45pm)