Celtic No 2 John Collins insists defender Virgil van Dijk will only be allowed to leave for "crazy" money.
Van Dijk has been linked with Ronald Koeman's Southampton.
Collins says no offers have been made as yet.
"Not as far as I know,' he said. 'But when you have got good players there is always going to be speculation and teams interested in them, so no problem with that at all.
"We would love to keep all the top players but everybody knows if crazy bids come in you never know. But at this moment in time we need them all playing for Celtic."
