If the Celtics decide to change the roster around Tatum and Brown, former NBA executive turned ESPN NBA front office insider Bobby Marks believes they’ll have multiple avenues to work out a trade. “When you have teams that still have all their first-round picks, then you certainly have to circle them,” Marks said on “The Lowe Post.” “Then you have Josh Richardson and Marcus Smart, $30 million in contracts there, certainly Horford’s a big number. And then you’ve got a mix of all these former first-round picks, so there are things there to get a deal done.