As the blockbuster trade sending Kevin Garnett and Paul Pierce to the Brooklyn Nets is hours from being official, christening the beginning of the Celtics’ rebuilding era, president of basketball operations Danny Ainge Wednesday watched his summer league squad tussle with the Houston Rockets, satisfied with his offseason work so far.

There are two standout rookies on the team, first-round pick Kelly Olynyk and second-round selection Colton Iverson, and an emerging player in former Missouri guard Phil Pressey.

The Celtics are trying to reduce their roster size, avoid any luxury taxes, and add youth to their roster despite the contracts of Gerald Wallace ($10.1 million owed next season), Kris Humphries ($12 m), and Keith Bogans ($5 m) coming over in the Brooklyn trade. Full story for subscribers.