Defending two-time champions Toulon face a tricky away game at Leicester in the third round of action in the European Rugby Champions Cup this weekend.
Fellow French giants Clermont travel to Irish province Munster, while Racing-Metro make the trip to Wales to play Ospreys.
Toulon warmed up for the Tigers clash in Pool 3 by beating Clermont to move back atop the highly competitive Top 14 table.
"This weekend it'll be the same level as Clermont if not more against Leicester at their ground," said Toulon hooker Guilhem Guirado.
"We're preparing for a massive game which will be decisive for Champions Cup qualification.
"They're a team based around a strong forwards game. In the backline they have a lot of power and speed. They remain a very English team, strong on the basics."
Toulon will likely leave out Wales full-back Leigh Halfpenny, with Argentina's Nicolas Sanchez taking over the fly-half role in the absence through injury of Australian duo Matt Giteau (groin) and James O'Connor (wrist).
Two-time European champions Leicester (2001, 2002) will join the elite trio of fellow former winners Leinster, Munster and Toulouse in hitting the one million home attendance mark in their 61st match at Welford Road on Sunday since making their debut in the 1996/97 season - and not missing one since.
Tigers flanker Jamie Gibson said the weekend's game didn't get any bigger.
"Playing against Clermont and Montpellier last year were a couple of huge games and Toulon are one of the best teams in Europe over the last few years," Gibson said.
"You can't play bigger games at club level. I can't wait."
Ulster host Scarlets in the pool's other game, both teams having been beaten by Toulon in the first two rounds.
Last year's beaten finalists Saracens travel to English Premiership rivals Sale in the tough Pool 1 topped by Munster ahead of Clermont.
In Pool 4, Glasgow travel to four-time former champions Toulouse, who will be without injured playmaker and ex-All Black Luke McAlister.
Glasgow will be on a high after their victory at Montpellier, who parted ways with forwards coach Mario Ledesma after that loss.
Pool 5 sees Ospreys welcome Racing-Metro to Swansea and Northampton, who should have Wales wing George North on board, away at Treviso.
Sunday's Pool 2 double-header features Wasps at Castres and Leinster travelling to Harlequins.
Source: AFP