The Lilywhites enter the contest on the back of a resounding 4-0 win over Crystal Palace in the Premier League, while the visitors travel to North London managerless following the sacking of Danny Cowley.
Match preview
Perhaps travelling to Selhurst Park in hope rather than expectation, Tottenham fans had witnessed their side labour to a draw with Brentford and succumb to a deserved defeat to Aston Villa before Antonio Conte's side turned on the style in their North London derby.
Harry Kane bagged a brace - taking him up to 198 strikes from 300 Premier League matches, a better record than Alan Shearer (196) had at that point - while Son Heung-min and Matt Doherty also made the net ripple in a comprehensive win for those in white.
Reigniting their top-four charge with a bang, Tottenham are still outside the Champions League places in fifth - two points behind Manchester United having played a game more - but an elusive piece of silverware will be on the menu if Conte's side can now make waves in the FA Cup.
Still without a major trophy since beating Chelsea in the 2008 EFL Cup final, Spurs have eight FA Cups to their name - the most recent of which came all the way back in 1991 - but they have suffered three successive fifth-round exits between 2020 and 2022.
Fourteen-time winners Arsenal were the last team to dump Spurs out in the third round in the 2013-14 season, and while the Lilywhites have only triumphed in one of their last five competitive home matches, their managerless visitors will not be expecting miracles on the North London soil.
A far cry from the famed FA Cup winners of 2007-08, Portsmouth - who now ply their trade in League One - have prepared for a trip to Tottenham by sacking manager Danny Cowley amid a miserable nine-game winless run in the third tier.
A 3-1 New Year's Day defeat to Charlton Athletic proved to be the final nail in the coffin for Cowley, who departs the South Coast side after helping them achieve just seven wins from their 22 League One games this season, seeing them languish in 12th place in the table.
Entering the 2022-23 FA Cup in the first round, Portsmouth have already seen off Hereford 3-1 and Milton Keynes Dons 3-2 to set up a third-round clash with Tottenham, but they have only progressed beyond this stage three times in 12 years since also reaching the 2010 final versus Chelsea.
If Portsmouth are to pull off the improbable and book a fourth-round place at the expense of Tottenham, they must become the first lower-league team since Nottingham Forest in 1975 to beat Tottenham away from home in the FA Cup, with Spurs winning 35 of their 43 such games since.
Portsmouth did overcome Tottenham 2-0 in the 2010 semi-finals, with Kevin Prince-Boateng and Frederic Piquionne netting extra-time goals at Wembley Stadium, but interim coach Simon Bassey will experience the true definition of a baptism of fire in North London.
Tottenham Hotspur form (all competitions):
W
W
D
D
L
W
Portsmouth FA Cup form:
W
W
Portsmouth form (all competitions):
L
W
L
D
D
L
Team News
Still plagued by attacking injuries, Tottenham remain without Richarlison, Lucas Moura and Dejan Kulusevski - whose muscular problem is more serious than first feared - while Rodrigo Bentancur is also nursing a groin problem.
On a brighter note, Yves Bissouma will be back from a one-game suspension and could be one of a multitude of changes for Tottenham, who will no doubt already have one eye on the North London derby with Arsenal on January 15.
Bryan Gil justified his start at Selhurst Park and should hold his spot up top, while Fraser Forster, Japhet Tanganga, Pape Sarr and maybe even Djed Spence could take to the field from the first whistle.
As for the visitors, experienced midfielder Marlon Pack received his marching orders for two bookable offences in the defeat to Charlton and will sit this one out through suspension, opening the door for Jay Mingi to return to the engine room.
It remains to be seen if captain Clark Robertson will overcome a hip injury in time to make the squad for this game, while Tottenham loanee Dane Scarlett will not be able to play against his parent club.
Ex-Arsenal right-back Zak Swanson can expect a frosty reception as he starts at right-back, while Blackpool loanee Owen Dale is also cup-tied and will play no part in this one either.
Tottenham Hotspur possible starting lineup:
Forster; Tanganga, Sanchez, Davies; Spence, Bissouma, Sarr, Sessegnon; Gil, Kane, Son
Portsmouth possible starting lineup:
Griffiths; Swanson, Raggett, Morrison, Ogilvie; Hackett, Morrell, Mingi, Hume; Koroma, Pigott, Jacobs
We say: Tottenham Hotspur 3-0 Portsmouth
The infamous new manager bounce is unlikely to make a difference for this Portsmouth side, who may set up defensively to try to frustrate Tottenham, but such efforts should prove futile.