The West London club beat Arsenal to the Ukrainian's signature, splashing out £62 million to sign Mudryk in January 2023.
However, the forward has failed to make an impact, scoring just seven goals in 58 appearances for the club.
Leboeuf has already lost patience with the 23-year-old and told BoyleSports he wouldn't even pay £1 million for him.
"Mudryk has no value anymore – he’s a lost cause and Chelsea won’t make any money on him," the World Cup winner said.
"He is so raw and he’s not getting better under many managers – there’s no improvement.
"Who would you want to buy Mudryk? I wouldn’t even buy him for ten million at the moment. In fact, I wouldn’t even buy him for £1m. Why would you want to spend money on a player who is not in any way productive.
"He’s been here 18 months and I know it’s been difficult for him given his circumstances at home in Ukraine, but judging from what I’ve seen, I really worry that Chelsea have signed a dud in Mudryk and they must replace him.
"I was bought for £2m in 1996 and I thought that was a lot! Mudryk was bought for £70m or something – it’s insane!"
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