With just two rounds of the Top 14 competition to go, Stade - the 2001 and 2005 Heineken Cup finalists - sit in seventh spot ahead of their trip to the Stade Felix Mayol to meet Toulon in Friday night's Amlin Challenge Cup semi-final.
"Toulon is probably one of the hardest places to go to in France win and, while obviously we play them in the Top 14 and know quite a bit about them, we know this Amlin Challenge Cup semi-final is certainly going to be a big ask for us," said Whitaker.
"But it is definitely a game we want to win and definitely a game we are really focusing on winning because winning the Amlin gives you the opportunity to play in the next Heineken Cup.
"And after going so close last year against Harlequins only to lose 19-18 we would love to win the tournament this year.
"Everyone wants to be in the Heineken Cup - it is one of the most amazing competitions in world rugby - and we want to be playing in that tournament and, although this is only the semi-final stage, we do have that alley back into that major competition."
Toulon won 34-8 at home in this season's Top 14 but Stade Francais held them to a 19-19 draw in the return fixture in Round 18 and the battle of the likely outside-halves Jonny Wilkinson and Felipe Contepomi looks set to be key on Friday night.
"Toulon have an amazing squad - they have got Test players all the way through," added Whitaker.
"They have got players like Jonny Wilkinson and Matt Giteau and it all depends on how they want to play the semi-final. Everyone knows Jonny plays more of a kicking game while Matt Giteau gives them another way of playing.
"And with players like Matt around him that opens up the field for Jonny and makes the team much more of an attacking threat.
"But Felipe is great for us, he provides us with our attacking spark, he is a game winner and a game changer and the guys love playing off him as well.
"We also have a lot of experience up front in players like Sergio Parisse, David Lyons and now George Smith as well so we have the players out there and hopefully we can put things together against Toulon because we will have to play really well and we know how difficult it is going to be down there.
"However, our results in the Amlin Challenge Cup show we have definitely focused on this tournament just as much as the Top 14. Like everyone else we try and win every competition we go into and that is what we are trying to do both in the Amlin and the Top 14.
"Unfortunately a few of the results have not gone our way in the Top 14 but we are still in the Amlin and after Friday's big semi-final we have got must-win games against Racing at Stade de France and then our final league game down in Biarritz."