 | HEINEKEN CUP POOL 4 |
The Gnoll, Neath
Saturday, 15 January
Kick-off: 1300 GMT
Live commentary on BBC Radio Wales and this website
The Ospreys' defeat in Munster cost them any chance of a Heineken Cup quarter-final place, but they can still help the Dragons' qualification hopes.
With Munster expected to win at Harlequins and top Pool Four, a Castres victory at The Gnoll would virtually guarantee them a best runners-up spot.
Northampton are favourites to claim one of the two runners-up places, with the Dragons in contention for another.
"We want to end our campaign on a win," said Ospreys team manager Derwyn Jones.
"We have a duty to our supporters and competitors to make sure we are competitive for all high-profile games, and the Heineken Cup as a competition deserves the respect of us picking our best team.
"We have a lot of pride to play for and feel that with a bit more luck we could have been going for a quarter-final place."
The Ospreys will be without Wales prop Duncan Jones, who is out for at least six weeks after injuring his thumb against Munster.
 | LAST MEETING |
Wales lock Brent Cockbain is struggling with a dead leg and starts on the bench, whilst young fly-half Matthew Jones is out with a head injury. Gavin Henson moves from centre to fly-half, with David Bishop starting in the midfield.
Back-up hooker Huw Bennett's injury woes have also continued with the news that his neck problem requires surgery that will keep him out for the rest of the season.
The Ospreys suffered a chastening 38-17 defeat away in Castres in their opening Heineken Cup game last October.
Wales forward Jonathan Thomas was sent off in the closing moments of that game for lashing out at Castres prop Mauricio Reggiardo after he had been held back.
Thomas received an 18-day ban for the offence, the punishment ruling him out of Wales' game with South Africa.
The Ospreys have denied rumours that they are interested in making a move for 31-year-old England and Wasps lock Simon Shaw. "He is a good player, but he is nothing to do with us," said Ospreys team manager Derwyn Jones.
Ospreys: S Terblanche; E Seveali'i, D Bishop, S Parker, S Williams; G Henson, J Spice; P James, B Williams (capt), A Jones, A Newman, J Thomas, A Lloyd, S Tandy, R Jones.
Replacements: R Hibbard, A Millward, C Griffiths, B Cockbain, R Pugh, M Jones, A Durston.
Castres: Metcalfe; Mola, Marticorena, Denney, Raffault; Delaigue, Albouy; Reggiardo, Vigneaux, Galasso, Nallet, Spanghero, Froment, R Capo Ortega, Volley.
Replacements: Argenese, F Capo Ortega, Deen, Bernad, Dourthe, Bory, Morlaes.
Referee: Tony Spreadbury (England)