The Celtics have grown accustomed to massive roster changes since the team dealt Kevin Garnett and Paul Pierce to the Nets in 2013, and with that comes familiarity with sequencing moves perfectly to maximize their roster under the current CBA.

On Monday, the Celtics rescinded Daniel Theis' qualifying offer, making him an unrestricted free agent according to Keith Smith. Theis agreed to a two-year, $10 million deal with the Celtics two weeks ago, so the only change here is the mechanism in which the Celtics will retain him.

Since Theis is now an unrestricted free agent, the Celtics can use Early Bird Rights to re-sign him to the agreed-upon $10 million. This, in turn, frees up additional cap space for Boston to use on their open 15th roster spot, which was opened when the team waived and stretched Guerschon Yabusele earlier this week.

Boston now has about $1.1 million in cap space to use on the last spot, and the series of moves made in order to create that space could clue us in on the Celtics' plans for the final roster spot.

One way the Celtics could go about this is to use the space to secure Tremont Waters on a four-year contract above the minimum salary. Signing a rookie above the minimum in this situation allows Boston to ink Waters for longer than two years.

The rookie second-round pick agreed to a two-way contract with Boston recently, so this could free up a two-way slot for someone else. Tacko Fall and Javonte Green both had strong Summer Leagues and could be worth a longer look in Maine next season.

Waters was a pleasant surprise in Summer League after he was selected with the 51st overall pick in the 2019 NBA Draft. While undersized at 5-10 and 172 pounds, there isn't much he can't do on the basketball court. Waters is shifty and smooth getting to the rim, has excellent skills in running an offense and is a pesky defender with quick hands and terrific instincts.

While he most likely won't get much of any playing time in his rookie season playing behind Kemba Walker, Marcus Smart, Brad Wanamaker and Carsen Edwards, that's a great group to work with every day and learn from. Waters won't have a limit on the amount of time he spends with the Celtics or Red Claws either.

The Celtics could go a number of different ways with their 15th roster spot, including bringing on an unrestricted free agent using a veteran minimum. But given the way they've worked to free up cap space by rescinding Theis' qualifying offer, it most likely points to Waters earning the last spot. Their next move would be finding a player to fill a vacated two-way slot along with Max Strus.

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