David Ribbans will make his Aviva Premiership debut when Saints head to Wasps on Sunday (kick-off 3pm).
The 6ft 8in English-qualified lock, who joined the club from South African outfit Western Province in January, takes the place of Christian Day in the Saints second row.
Day is not in the matchday squad and neither is Calum Clark, with the flanker replaced by Jamie Gibson.
Those are the only two changes to the Saints side that lost to Leicester Tigers at Franklin’s Gardens last time out.
It will be a big day for Ribbans, who scored a hat-trick in a recent friendly win against Bedford Blues at Goldington Road.
The 21-year-old has only made two Saints appearances so far, with both of those coming in the Anglo-Welsh Cup pool stages.
Meanwhile, Wasps, who have not lost a league game at home since December 2015, have opted to rest England flanker James Haskell.
They have also reshuffled their backline after last Saturday’s Champions Cup quarter-final defeat at Leinster, with Jimmy Gopperth switching from centre to fly-half and Joe Simpson coming in for Dan Robson at scrum-half.
Last weekend’s half-back pairing, Robson and Danny Cipriani, are on the bench.
Former Saints prop Paul Doran-Jones, who has joined on a one-week loan from Gloucester, is also among the replacements for the current league leaders.
Wasps: Le Roux; Wade, Daly, Beale, Bassett; Gopperth, Simpson; Mullan, Taylor, Swainston; Launchbury (c), Myall; Johnson, Young, Thompson. Replacements: Cruse, Bristow, Doran-Jones, Symons, Hughes, Robson, Cipriani, Leuia.
Saints: Tuala; North, Tuitavake, Mallinder, Foden; Myler, Groom; A Waller, Hartley, Brookes; Lawes, Ribbans; Gibson, Wood (c), Picamoles. Replacements: Haywood, E Waller, Hill, Ratuniyarawa, Harrison, Dickson, Burrell, K Pisi.