VfB Stuttgart chief Sven Mislintat has warned interested clubs that Sasa Kalajdzic won't be allowed to leave late in the summer market.
The centre-forward has been linked with Chelsea and Tottenham.
But Mislintat told Kicker: "It is not possible at any time, but only with our consent, therefore: no. I would be worried if we hadn't already generated €38.5m (from sales)."
Asked specifically whether an offer of €30m on August 31 could force a rethink, Mislintat added: “Then that would be two no's: getting a replacement at such a late point in time is very difficult or even impossible.
"And 30 million would not be enough."
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