Worcester Warriors flanker Richard de Carpentier will get his second Premiership start of the season against Northampton at Sixways on Saturday.
The 23-year-old will line-up alongside Sam Betty and captain Jonathan Thomas in the back-row against a side who have lost just one Premiership game all season.
Mariano Galarza returns from international duty to partner James Percival in the second-row, while the rest of the forwards remain unchanged from the clash with Sale Sharks last weekend.
In the backs, Paul Hodgson replaces the injured Jonny Arr at scrum-half, with Ignacio Mieres at number ten.
Dean Hammond and James Stephenson retain their starting berths on the wings but Josh Matavesi returns to the backline for the visit of last season's Aviva Premiership finalists.
Max Stelling could be in line for his first-ever Aviva Premiership appearance after being named amongst the replacements, while Jeremy Su'a could make his first Warriors appearance for over a month from the bench.
Worcester coach Carl Hogg is confident De Carpentier will give a good account of himself against the Saints.
"Injuries give an opportunity for someone like Richard to come in and operate against a top-class team," he said.
"Richard and Sam Betty in the back-row will give us lots of collision and energy in the back-row and we need that because Saints' back five in the scrum are strong.
"We'll need to get round the corner and these guys have a lot of endeavour.
"Also, with David Lemi out it gives an opportunity for players like James Stephenson and Dean Hammond, which is important for the future of the club. They will certainly be tested this weekend."
Form: Worcester Warriors' only victory in any competition this season was 21-16 at Cardiff Blues in the LV= Cup on 8th November. The Warriors have not been victorious at their own Sixways ground since London Wasps were the visitors in the Premiership on 1 March. Northampton Saints have lost only once since late September: 13-19 at Castres in the Heineken Cup. The Saints solo away loss in the Premiership this season was 24-26 at Gloucester in round 3. Worcester's only victory in their last eight clashes with Northampton was 12-3 at Sixways on 30 September 2011. The Saints record at Worcester in the tournament is a creditable won five, lost two.
Worcester Warriors: 15 Chris Pennell, 14 James Stephenson, 13 Alex Grove, 12 Josh Matavesi, 11 Dean Hammond, 10 Ignacio Mieres, 9 Paul Hodgson, 8 Jonathan Thomas (c), 7 Sam Betty, 6 Richard de Carpentier, 5 Mariano Galarza, 4 James Percival, 3 Rob O'Donnell, 2 Chris Brooker, 1 Ofa Fainga'anuku.
Replacements: 16 Ed Shervington, 17 George Porter, 18 John Andress, 19 Mike Williams, 20 Chris Jones, 21 Jeremy Su'a, 22 Paul Warwick, 23 Max Stelling.
Northampton Saints: 15 Glenn Dickson, 14 Ken Pisi, 13 Dom Waldouck, 12 Luther Burrell, 11 Tom Collins, 10 Stephen Myler, 9 Lee Dickson, 8 Sam Dickinson, 7 Tom Wood, 6 Calum Clark, 5 Christian Day, 4 Samu Manoa, 3 Salesi Ma'afu, 2 Dylan Hartley (c), 1 Alex Waller.
,Replacements: 16 Mike Haywood, 17 Ethan Waller, 18 Tom Mercey, 19 Courtney Lawes, 20 Phil Dowson, 21 Alex Day, 22 Vasily Artemyev, 23 Tom Stephenson
Date: Saturday 30th November
Kick-off: 1500 (local and GMT)
Referee: Tim Wigglesworth
Assistant referees: Paul Dix, Stuart Terheege
TMO: David Sainsbury