The European Rugby Champions Cup begins this weekend, with a star-studded Toulon bidding to become the first side to win four straight European titles.
Two-time Heineken Cup winners Leicester Tigers get this season's competition under way when they take on Stade Francais in a rematch of the 2000-01 final at Welford Road on Friday.
But it is Toulon who will be the team to beat in the second edition of the Champions Cup after winning the inaugural tournament - having previously won the last two Heineken Cups - with a 24-18 victory over Top 14 rivals Clermont-Auvergne in the Twickenham final.
A host of international stars have been brought into the Toulon ranks since that triumph, with New Zealand's Ma'a Nonu, South Africa number eight Duane Vermeulen, Australia fly-half Quade Cooper and former Ireland lock Paul O'Connell all making the move to the Stade Mayol.
Toulouse are the only team to win the European title four times, but to do so in consecutive years would be an unprecedented achievement for Toulon, having become the first side to lift the trophy for a third straight year back in May.
However, their form in the Top 14 has been anything but consistent. Toulon have four wins and four losses in the first eight domestic games and have been drawn alongside fellow three-time winners Leinster and Premiership sides Bath and Wasps in Pool 5, which is considered to be the tournament's 'Pool of Death'.
The tough nature of the draw and a lengthy absence for O'Connell, who could be out for as long as eight months with a hamstring injury sustained in the Rugby World Cup, means Toulon are not favoured to lift the trophy.
Instead it is Clermont who approach the season as the bookmakers' early favourites having come up short in last season's showpiece as well as in the 2012-13 final.
With European Player of the Year Nick Abendanon and the likes of Wesley Fofana and Morgan Parra in their ranks, Top 14 leaders Clermont have the talent and the pedigree to go far and win the competition for the first time.
Standing in their way in Pool 2 are Ospreys, Exeter Chiefs and Bordeaux-Begles, while Toulouse - second in the Top 14 after recording six wins from eight - are pitted against Ulster, Saracens and tournament debutants Oyonnax in Pool 1.
Pro12 champions Glasgow Warriors are in Pool 3 alongside Northampton Saints, Racing Metro and Scarlets, but coach Gregor Townsend has issued a stark warning ahead of the start of their campaign at Racing.
He said: "We have to be at our best, or close to our best, in the six games of the European Champions Cup or we won't get out of our pool, that is the reality any team in the Champions Cup faces."
The biggest outsiders to progress from their pool are Benetton Treviso. The Italian side are in Pool 4 with Munster, Leicester and Stade Francais who, after defeating both Toulon and Clermont en route to Top 14 glory last season, should be hugely confident of ending the reigning champions' European dominance.