Faverani, 25, played for Valencia Basket in Spain last season and averaged 9.3 points and 4.6 rebounds a game. Celtics had been looking into the 6-foot-11 forward for the past couple of weeks and officially signed him a 3-year deal worth $6 million.
Pressey, averaged 9.4 points, 6.6 assists and two steals per game this month as a member of the Celtics' summer league roster. The 5-foot-11 guard is signed to a non-guaranteed contract and will fight for a spot on this year's 2013-14 Celtics roster.
At Missouri, Pressey averaged 12 points and seven assists as a junior. He was a finalist for the NCAA Bob Cousy Award given to the best point guard in the nation.