Leicester striker Leonardo Ulloa has handed in a transfer request
Ulloa has asked to leave the champions with Spanish club Alaves waiting to pounce after failing with a £5m bid this week.
Ranieri says the Argentine striker will only leave for big money and insisted the 30-year-old will knuckle down if the Premier League champions force him to stay.
West Ham playmaker Dimitri Payet told his club this month he did not want to play for them any more.
Claudio Ranieri is confident Ulloa will knuckle down if they choose to keep him at the club
And Chelsea striker Diego Costa missed their game at Leicester after big-money interest from China, although boss Antonio Conte blamed a back injury for his absence.
But Ranieri says Ulloa will react well if Leicester keep him.
"I don't know the future but there are rules and the players can't refuse [to play]," said Ranieri. "Everybody must respect these rules.
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"If he stays he will be OK. He is a professional and we can't be professional just at the end of the week or the month to bring the money.
"He must understand if he goes we need another striker and if we want to buy another striker that means a lot of money.
"If I lose him then someone must arrive so it is important the club is happy with the money we receive.
"Leo is a very good player if someone wants him they must pay the money. I think at the end Leonardo will stay with us. I want him to."