jim davis/globe staff

Jeff Green was surrounded by green basketballs to sign at the Celtics’ Media Day at the team’s facility in Waltham.

jim davis/globe staff

First-round draft pick Kelly Olynyk smiled while doing a radio interview. Players posed for photos, did promos, and answered questions from reporters.

jim davis/globe staff

Gerald Wallace listened to instructions while doing a promotional video.

jim davis/globe staff

Head coach Brad Stevens filmed a promotional video during which he was told to try to appear as if he was stressed on the sidelines.

jim davis/globe staff

Jared Sullinger had a laugh during a television shot.

jim davis/globe staff

Team president Danny Ainge was at the event.