Toulon have shrugged off claims that their former Welsh prop Eifion Lewis-Roberts failed a drugs test after the Top 14 Final.
Lewis-Roberts, who now plays for Sale in the Aviva Premiership, could face a two-year ban after sports daily L'Equipe claimed he tested positive for morphine and pseudoephedrine.
"I don't believe he's a guy who dopes," said Toulon president Mourad Boudjellal.
"He could have taken something to ease pain."
Toulon coach Bernard Laporte admitted that if the allegations were true, he too would be shocked.
"This would surprise me but if it's true, I'd be very disappointed by the man," he said.
"I worked with him for seven months and I have a lot of admiration for him as a player. He made a lot of effort to lose weight, to be fit and bring something to the team."
Toulon have battled doping allegations in the past.
In November last year, English flanker Steffon Armitage, who tested positive for morphine five months earlier, was cleared of any wrongdoing by the French Rugby Federation's appeals commission.
Armitage failed a test for the banned substance after the same match which Toulon lost 18-12 against Toulouse on June 9.
The club always maintained the test showed an "abnormal" result as a side-effect of painkillers and anti-inflammatories which Toulon's medical staff had prescribed Armitage for back pain.