Ryan, 23, spent last season with the Celtics on a two-way deal, spending nearly all of his time in the G League with the Grand Rapids Gold and Maine Celtics. He appeared in one game with Boston.
In 30 G League games, he averaged 19.4 points on 47 percent shooting, including 41 percent on 3-pointers. He averaged 19.0 points in two summer games with the Celtics before going down with a sprained ankle.
Exhibit 10 contracts count toward a team’s offseason roster limit of 20, but not toward the regular roster unless the player receives a standard deal.