Meanwhile, the hosts will be hoping to produce a positive response after suffering a narrow defeat to Derby County last weekend.
Match preview
Middlesbrough are competing in the Championship for an eighth consecutive season after having to settle for an eighth-place finish last season.
Michael Carrick's side are looking to mount a promotion bid this term and the Boro boss would have been encouraged to see his side start the campaign with a narrow 1-0 win over Swansea City.
They backed up that result with a commanding 3-0 away win over Leeds United in the EFL Cup, before they were quickly brought down to earth in last Saturday's league meeting with Derby County at Pride Park.
Boro had 70% possession and racked up 20 shots in their away clash with the Rams, but those numbers counted for very little as they fell to a narrow 1-0 defeat following Kayden Jackson's 14th-minute strike.
After losing to one newly promoted side last weekend, Middlesbrough will be keen to avoid a similar fate in Saturday's clash against League One champions Portsmouth - a team they have not faced since recording a 3-1 away win in March 2012.
Portsmouth boss John Mousinho is still waiting for his first Championship win as a manager, having his side drew both of their opening two league games.
Pompey began their first Championship campaign since 2011-12 with an entertaining 3-3 draw, before they fell to a narrow 1-0 home defeat in their EFL Cup clash with Millwall.
They then had to settle for a goalless draw in last Saturday's league game against Luton Town despite playing over an hour with a numerical advantage following Thomas Kaminski.
Portsmouth are now preparing for a long trip to the North East, and they may be able to draw inspiration from the fact they finished the 2023-24 campaign with the best away record in League One after winning 13, drawing eight and losing just two of their 23 road trips.
Although they have not won at the Riverside Stadium since August 2006, they have managed to avoid defeat in each of their previous three away games against Boro.
Middlesbrough Championship form:
W
L
Middlesbrough form (all competitions):
W
W
L
Portsmouth Championship form:
D
D
Portsmouth form (all competitions):
D
L
D
Team News
The hosts are likely to be without the services of Darragh Lenihan and Dael Fry, who have been forced to miss the first three games of the season through injury.
Jonny Howson is expected to be sidelined for a few weeks after picking up a hamstring issue in the EFL Cup win over Leeds.
Having missed the last two matches, midfielder Riley McGree is hoping to prove his fitness in time for Saturday's home fixture.
As for the visitors, they are likely to be without Tom McIntyre, Regan Poole, Jacob Farrell, Josh Murphy, Colby Bishop and Kusini Yengi, while Samuel Silvera is ineligible to face his parent club.
Mousinho has revealed that Marlon Pack is a doubt for Saturday's contest despite passing the concussion protocols following a collision with teammate Owen Moxon last weekend.
Goalkeeper Nicolas Schmid and midfielder Abdoulaye Kamara are in contention to make their Pompey debuts after arriving from BW Linz and Borussia Dortmund respectively.
Middlesbrough possible starting lineup:
Dieng; Ayling, Van den Berg, Clarke, Engel; Hackney, Morris; Jones, Azaz, Burgzorg; Latte Lath
Portsmouth possible starting lineup:
Schmid; Williams, Shaughnessy, Towler, Ogilvie; Dozzell, Kamara; Lane, Lang, Richie; Sorensen