Toulon were Amlin Challenge Cup finalists in 2010, while Harlequins won the title last year for the third time. It truly is a battle of two of the current giants of European rugby. Everywhere you look there are high-level match-ups.

Jonny Wilkinson v Nick Evans would have been worth the entry fee alone, while Nick Easter clashing with Joe van Niekerk and Steffon Armitage in the back row is another of the great prospects. And what about Mathieu Bastareaud against Jordan Turner-Hall in the midfield - explosive!

Throw in Carl Hayman and Matt Giteau for Toulon, and Danny Care, Ugo Monye and Mike Brown for Quins, and you have all the ingredients for a world class contest at Stade Felix Mayol.

Toulon dropped only one game in qualifying from a Pool that contained Petrarca Padova, Lyon Rugby and Newcastle Falcons - a narrow defeat at a windswept Kingston Park against the Falcons. Unbeaten at home since 3 September - ASM Clermont Auvergne are the only team to win at Felix Mayol this season - Toulon will be backed by 14,500 fervent supporters as they try to take a step closer to a major title.

They haven't lost a European encounter on home turf since falling to Northampton Saints in 2009, but English Premiership leaders Harlequins have proved they have no problem overcoming formidable opposition on the road.

They beat Munster at Thomond Park on the way to last year's Amlin Challenge Cup final, Toulouse at Stade Ernest Wallon in this season's Heineken Cup and only last week they toppled Saracens at Wembley in front of a world record club crowd of more than 82,000.

Harlequins director of rugby Connor O'Shea expects a full-blooded encounter in the south of France but admits his players are desperate to defend their crown after dropping down from the Heineken Cup.

"Toulon are a ferocious animal in their own back yard. We are massive underdogs going into this game - you just have to look at their record at home. The mood in camp is very good. We feel comfortable with where we are but we know the next challenge against Toulon is bigger than any we have faced," said O'Shea..

"It's an enormous game but there's a home semi-final at the Stoop up for grabs. That's huge for the players. They're playing to defend the title which they took in such a hard manner last season.

"That meant so much to them and it would mean a lot again this year. But all of that is irrelevant as Toulon is as big a test as we've faced all year and it's in a place which is tough for any team to get anything."