Who steps into Garnett's place for the 2013-14 season will likely be the player that presents the best opportunity to win right now, while also preferring youth over older talent.
The Celtics are clearly building toward the future, so if one of their veterans doesn't have a clear upside over a younger player, Boston might be more inclined to start the latter.
Ahead is a breakdown of the power forward position, including their role, strengths, weaknesses and projected minutes.
*Note: The minutes section for each player is assuming either Bass or Humphries gets traded before the end of the season.
Role: Sullinger will face a tough road ahead, as he returns from back surgery and attempts to establish himself in Boston's rotation yet again.
After making mostly spot starts early in his rookie year, Sullinger obtained the starting gig at power forward for only two games before going down for the season.
He'll likely start the season off as a bench player as he works his way into shape from last season's back surgery.
It's safe to say Sullinger will earn the starting spot at the four early in the year and he could eventually find himself in an undersized starting position at center—especially if Bass or Humphries is moved—where Boston has nearly no depth.
Strengths: In his first year, Sullinger was a do-it-all player. He was decent on the defensive end, a fantastic rebounder at both ends, and he seemingly always found a way to get the ball in the basket.
Weaknesses: Sullinger's injury history is a huge question mark, and his weight was an issue last season. According to Gary Washburn of the Boston Globe, Sullinger has gained a few pounds while recovering from surgery, but he's back in Waltham at the Celtics training facility, working to get his weight down and get back in shape.
Role: Like Sullinger, Bass will likely shift between the center position and the power forward position. Bass played significant minutes behind Garnett at the five last season and is one of the better options at the position next season.
He'll start the year as a starter at the four, but the Celtics will most likely look to move him from opening night. If they can't trade him, he could shift over to the center position in the starting lineup when Sullinger is at full strength.
Strengths: He's a solid rebounder and his ability to shoot off the pick-and-pop makes him an excellent compliment to point guard Rajon Rondo.
Weaknesses: Bass has struggled to find the open man and couldn't protect the rim last season. Without significant minutes, Bass couldn't find rhythm on offense or defense, either.
Role: In the final year of his contract, Humphries will be looking to re-establish himself as a suitable rebounder and scorer.
According to Basketball-Reference.com, Humphries averaged more than 10 points and rebounds over his first two full seasons in New Jersey. Last year he was relegated to the bench, where he saw his numbers plummet.
He'll step in as the starting center, but should also split time as a power forward, pairing with the likes of Bass and Sullinger.
Strengths: Humphries has range, he can block shots and he can play on the block. He's playing in a contract year and is expected to be motivated heading into the season.
Weaknesses: His confidence may be shaken after what was a frustrating season in Brooklyn. Humphries isn't an extremely talented offensive or defensive player, but he gets the job done.
Role: Olynyk is the mystery man of the 2013-14 season. Stevens could use the No. 13 overall selection in a variety of roles, including starter at the four or five, rotational player or, if it was up to Brian Scalabrine at CSNNE.com, at small forward.
Olynyk will start the season off the bench, but if Bass or Humphries becomes a mid-season casualty, he would surely step in at power forward, with Sullinger moving to center.
Strengths: The rookie is versatile as a 7-footer, displaying incredible range for a big man and a remarkable ability to finish around the rim despite his thinner frame. He's extremely intelligent, which makes up for his lack of pure athleticism.
Weaknesses: Olynyk isn't a great rebounder and he doesn't have good feet. He lacks lateral quickness and doesn't have the explosiveness needed to pound down low with bigger, NBA-caliber talent.