The 30-year old striker, who has netted 12 Scottish Premier League goals this season, is being linked with a return to the City Ground this winter but Johnston says nothing has landed in the Rugby Park inbox thus far.
"Billy Davies had Kris down at Forest but so far we've had no contact," Boyd told the Sunday Mail.
"We want to keep Boydy because he is a top player. It's not just his goals, he is a big influence to the younger boys. They can see that he has played at the top."
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