Clermont's former New Zealand sevens international Fritz Lee warned against "writing off" Toulon and their packed fixture list ahead of Saturday's home French Top 14 fixture.
The visitors, who are also eyeing the end of season play-offs, will arrive at Stade Marcel Michelin for their third match in eight days due to Covid-19 postponements and were beaten by lowly Montpellier midweek.
"You can never write them off. They're a quality side and they're fighting for the top six as well," Lee told AFP on Wednesday.
"It's a massive advantage for us. They'll be licking their wounds after Tuesday's game. We have everything for us, everything against Toulon," he added.
Samoan-born Lee, 32, has been unable to represent the Pacific Island nation due to his appearances for the All Blacks sevens outfit more than a decade ago.
No 8 Lee said he would like to see an evolution in international rugby's eligibility regulations to allow players to feature for two Test sides.
"There are quite a few players in Europe that would love to represent their country of birth," Lee said.
"We've tried for many years, but they (World Rugby) are trying to make it difficult for everyone.
"I'm not quite sure they'll change it any time soon. If it was to happen it would be great," he added.
The former Chiefs back-rower is in his eighth season at Clermont but they have managed to win more than two games on the bounce on just two occasions this campaign.
They are fourth in the table with three matches of the regular season remaining in coach Franck Azema's last term in charge after 11 years with the 2017 champions.
"It's been tough for everyone. It's been a stressful, long rollercoaster this year," Lee said.
"Him leaving on a high note would be an ideal situation for himself and us. He's been great for the club.
"If we do go all through to the end it will be massive for him. And for the players as well," he added.
Shut 'Ice' down
This weekend Lee will meet former club team-mate and ex-All Blacks fullback Isaia Toeava, who joined the three-time European champions last summer after five years with Clermont.
"He's a high quality player. He's probably the main player for Toulon," Lee said.
"We have to shut him down. 'Ice' knows Clermont inside and out. It's going to be tough for us to put pressure on him," he added.
Elsewhere, Springbok flyhalf Handre Pollard's Montpellier will be without 15 injured players, including the Rugby World Cup winner, as they look to take another step securing their top-flight safety with a trip to Stade Francais.
Leaders Toulouse are likely to continue to rest players ahead of next weekend's European Champions Cup final as they host struggling Bayonne.
Their opponents next Saturday, La Rochelle, face a third match in eight days, and could also name a weakened side as they welcome already-relegated La Rochelle.
Fixtures (SA times)
Friday
Pau v Racing 92 (20:45)
Saturday
Bordeaux-Begles v Castres (14:45), Toulouse v Bayonne, La Rochelle v Agen, Lyon v Brive, Stade Francais v Montpellier (all 17:00), Clermont v Toulon (21:05)