This is not up to Smart, and it really isn't under Ainge's control either. This is about the market for his services, and there are only a handful of teams who could even consider paying him over $10M. This is a bad year to hope someone overpays you.
The only way Marcus sticks here long term is if he takes a deal less than $10M. If we match an offer that is higher than that, it can't be much higher, because Ainge will absolutely have to move him. If he gets an offer for $14M we do not match, because we don't have the minutes to make him an attractive player at that price, and there is no way he can stay.