For the first time since the Big Three were originally conceived, the Celtics  will have a new shooting guard lining up alongside Rajon Rondo , Paul Pierce  and Kevin Garnett . Not since Kendrick Perkins  was traded to Oklahoma City have the Celtics undergone such an important change.
Ray Allen ‘s departure for Miami was really the culmination of a transformation that was beginning to take shape last season. With Avery Bradley  in the starting lineup, the Celtics suddenly became a dynamic defensive team that could also score points at a better-than expected rate. The C’s outscored their opponents by almost 20 points per 100 possessions with Bradley in the starting lineup.
Small sample size or no, Bradley’s emergence help point them in a direction that was less dependent on Allen’s shooting and off-the-ball movement, and increasingly reliant on Rondo’s gift for creating offense for others. In an interesting twist, the Celtics tried desperately to re-sign Allen, but when those efforts failed they turned their attention toward completing the transition toward a more versatile and potentially dynamic backcourt.
Terry is a scorer, capable of creating his own shot and also adept at knocking down 3-pointers. Just one season removed from a championship run with the Mavericks, Terry has his share of big-shot pelts on his wall. He also comes with the added bonus of providing solid backup point guard play. All areas where the C’s needed help.
Terry’s scoring will help offset the loss of Allen, but what’s interesting — as Kirk Goldsberry noted in a Court Vision post  — is that they shoot from very different parts of the court. In Terry, the C’s now have a mid-range creator, something that has been notably missing the last few years beyond Paul Pierce.
Lee, on the other hand, is a defensive presence at 6-foot-5. He’s not known as a scorer, yet he’s usually good for 10 points a game, along with a handful of rebounds and assists.
The fifth-year guard is a connoisseur’s player. He’s active off the ball on offense and a strong cutter. He can run the floor and finish, and while he doesn’t get a lot of opportunities to score, he knows what to do with the ones he has. Lee rarely turns the ball over and is a career 38-percent 3-point shooter. He is also particularly adept at making corner 3’s, which were an Allen specialty.
Both Terry and Lee average about 30 minutes a game and there should be ample time for both, pssobly even in three-guard lineups. Who starts will be a matter of mild interest, but Lee will likely assume the job with Terry operating as a sixth man — a role he’s thrived on over the past five seasons.
Keyon Dooling  is also back and while the veteran provided a sage-like locker room presence, he often struggled to find a consistent role. Yet Dooling settled in nicely during the playoffs as a high-energy defensive change-up. The Celtics need the professional depth provided by Dooling because Bradley’s status is up in the air.
There is no timetable for Bradley’s return from double shoulder surgery and there is good reason to be cautious. Still only 21 years old, the third-year guard has already dealt with a severe ankle injury and the reoccurring shoulder problems that were a constant worry during the postseason. With the added depth, Bradley can take the time to heal properly.
When he returns, Doc Rivers  could have a surplus of qualified backcourt members competing for playing time. That’s assuming, of course, that everyone is healthy. These things have a way of working themselves out over time and the last thing the Celtics are going to worry about going into the season is having too much depth.
They will also have Jamar Smith, who averaged 13.6 points and 5 assists for the Red Claws in the D-League, while making over 43 percent of his 3’s. Dionte Christmas and Kris Joseph are both wing players who add some needed athleticism and offensive potential. All three are on non-guaranteed contracts and at the moment there are two roster spots available. Cracking the rotation will be difficult no matter who makes the cut, but the C’s needed to get younger and all three have potential as NBA contributors.
How it all works with Rondo will be one of the key questions for the upcoming season, but on paper the Celtics seem to have upgraded the backcourt, added depth and signed two players who should complement the mercurial point guard’s game.