Contract extension for Tyler Zeller?

The Celtics and Zeller have talked about a deal and there is a belief if Zeller wants to lock in security, the C’s would be open to a deal. The problem is if Zeller wants to maximize his value he may have to take a trip through restricted free agency. There is a deal possible between Zeller and the Celtics; it’s about 50/50, according to sources close to the process.
via Basketball Insiders
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