It's crucial the Scarlets come away with something from the game after losing their opening pool match last weekend to Harlequins and Thomas, who recently broke through the 100-game barrier for the region, is confident his pack can apply the squeeze on the French unit to provide the ammunition for the Scarlets backs.
"Sometimes when you take that away from a French team it really does affect them" he said. "It will take all eight of us to be switched on to get anything out of the game."
"We know they have a massive squad and a massive budget," he added. "That allows them to develop strength-in-depth and they have very good players. We just have to get stuck into them and we cannot afford to ease off on them."
Scarlets coach Nigel Davies admitted there have been a lot of soul searching after last week's shock reversal to Quins.
"We have been very open and honest this week, we realise as a group what went wrong against Harlequins and hopefully we can take those lessons on board against Stade," he said.
"Stade are a very competitive team and it's a difficult place to go but both those points are hugely motivating for our team. The mindset is that we've got to go there to try to get a result. We've got to be confident in our own ability and confident that - as individuals and a team - we can compete against a Stade XV full of world class players.
"We know that it will be backs against the wall stuff but we go there with a real fighting mentality and I'm comfortable that I'm putting out a very good team and that as a group we'll be fired up for this encounter."
The match will be a baptism of fire for rookie second row Dominic Day. The 23-year-old will be starting his first Heineken Cup match but skipper Simon Easterby is confident the youngster will handle the intimidating atmosphere.
"Dom is a superb athlete and this is a great chance for him. He has to front up as there will be no hiding place for him but I'm sure he will handle it," said Easterby.
Scarlets 15 Morgan Stoddart 14 Darren Daniel 13 Regan King 12 Gavin Evans 11 Mark Jones 10 Stephen Jones 9 Martin Roberts; 1 Iestyn Thomas 2 Matthew Rees 3 Kees Meeuws 4 Dominic Day 5 Scott MacLeod 6 Simon Easterby (capt) 7 Gavin Thomas 8 David Lyons
Replacements: 16 Ken Owens 17 Phil John 18 Dafydd Jones 19 Johnathan Edwards 20 Sililo Martens 21 Ceiron Thomas 22 Rob Higgitt