Leinster head coach Leo Cullen believes the power of Toulon wore his men down as the Irish side lost 20-16 in their Champions Cup clash in Dublin.
This was Leinster's fourth successive defeat in the pool and ends their slim hopes of progression, despite a solid first-half on Saturday.
But after the break the reigning champions scored 15 unanswered points to edge a win in front of close to 45,000 fans at Aviva Stadium.
"It is just the power of Toulon that unfortunately wears you down," Cullen told EPCR's website.
"I thought we defended pretty well in the early part of the second half but they just wore us, picked up our penalties and kicking for the corners.
"It meant we were defending against big bodies and then you have the power coming off the bench – like Juan Fernandez Lobbe and Mamuka Gorgodze – the list is endless.
"There was a lot of endeavour in the first half but the pure quality they have wore us down in the end.
"Now we need to focus on the PRO12 and then see where we are when we start up again in Europe."