Baynes has been a valuable piece for the Celtics, and has even added the corner 3 to his game. While I don't think this choice is obvious for Baynes, I predict his agent, Marc Fleisher of Entersport, will recommend he opt in to the final year of his contract. Baynes could potentially struggle to find more than this in tough center market next summer, and seems to enjoy his role on this current Celtics squad.