WORCESTER Warriors will be without scrum-half Francois Hougaard and flanker Sam Lewis through injury for Sunday's clash with Leicester Tigers at Sixways (3pm).

Hougaard has failed to recover from an ankle problem in time to face Tigers while Lewis has sustained a hamstring injury.

But Worcester will be boosted by the return of fit-again duo Jackson Willison and Jack Singleton.

Warriors also welcome back Jonny Arr, Will Spencer and David Denton into the starting line-up as they look to bounce back from last weekend's defeat at London Irish.

Gerrit-Jan van Velze will captain the side at number eight as Donncha O'Callaghan has been dropped to the bench.

Willison steps back in for Chris Pennell in the centre next to Ryan Mills, while Pennell returns to full-back.

Josh Adams and Bryce Heem start on the wings while stand-off Jamie Shillcock is joined by scrum-half Arr, who will make his 199th club appearance as he deputises for crocked number nine Hougaard

In the front row, Singleton returns to join Ethan Waller and Nick Schonert while Spencer is restored to the starting 15 next to Darren Barry in the second row.

Denton returns to the back row in place of Lewis and lines up next to Alafoti Faosiliva and GJ van Velze – the latter of whom skippers the side.

The bench includes academy centre Will Butler, who will make his Premiership debut if he comes on.

The 19-year-old recently captained England Under 20s in their 6 Nations campaign while he has also led Warriors in the Anglo-Welsh Cup this season.

Tom Youngs and Mathew Tait return to Leicester's line-up for the trip to Worcester.

Club captain Youngs swaps places with Tatafu Polota-Nau to start in the front row, while Tait takes over from Gareth Owen in midfield.

In the only other change to the squad from the side that beat Saracens last weekend there is a place among the replacements for Nick Malouf on his recovery from injury.

Mike Williams will make his 50th appearance for the club since a move from Warriors in the summer of 2015.

Warriors

15 Chris Pennell 

14 Bryce Heem 

13 Jackson Willison 

12 Ryan Mills

11 Josh Adams 

10 Jamie Shillcock 

9 Jonny Arr 

1 Ethan Waller 

2 Jack Singleton 

3 Nick Schonert

 4 Darren Barry 

5 Will Spencer

6 David Denton 

7 Alafoti Faosiliva 

8 GJ van Velze (C).

Replacements

16 Kurt Haupt 

17 Ryan Bower 

18 Gareth Milasinovich 

19 Donncha O’Callaghan 

20 Matt Cox 

21 Luke Baldwin 

22 Will Butler

23 Dean Hammond

Leicester Tigers

15 Telusa Veainu

14 Adam Thompstone

13 Manu Tuilagi

12 Mathew Tait

11 Jonah Holmes

10 Matt Toomua

9 Sam Harrison

1 Greg Bateman

2 Tom Youngs (c)

3 Logovi’i Mulipola

4 Mike Fitzgerald

5 Graham Kitchener

6 Mike Williams

7 Brendon O’Connor

8 Sione Kalamafoni

Replacements

16 Tatafu Polota-Nau

17 Michele Rizzo

18 Pat Cilliers

19 Harry Wells

20 Luke Hamilton

21 Harry Simmons

22 Joe Ford

23 Nick Malouf