With the season fast approaching and the rotation solidifying, the Celtics still have some roster work to do. Below are some scenarios and the options that Boston has within each.

Who makes the 15 man roster?

This one has been talked about almost ad nauseum since Boston signed Demetrius Jackson to a fully guaranteed contract for the 2016-17 season. That signing, combined with the other offseason work Danny Ainge has done, has put Boston at 16 fully guaranteed contracts on the books. A team can only carry 15 on their roster without an exception from the NBA, which Boston does not qualify for. This means someone has to go, and the Celtics will have to trade or eat a contract.

The locks to make the team are: Avery Bradley, Jaylen Brown, Jae Crowder, Al Horford, Jonas Jerebko, Amir Johnson, Kelly Olynyk, Terry Rozier, Marcus Smart, Isaiah Thomas and Tyler Zeller. That leaves four spots for the taking.

Competing for the last four spots has been: Ben Bentil, Marcus Georges-Hunt, Gerald Green, R.J. Hunter, Demetrius Jackson, Jalen Jones, Damion Lee, Jordan Mickey and James Young. You can confidently take Georges-Hunt, Jones and Lee out of the mix. Those three players are ticketed for Maine in the D-League (more on that later).

That leaves us with six players for four spots. Jackson and Mickey are probably locks. Both provide depth and are on team-friendly contracts. Green has played well enough to make it as a veteran scorer/shooter off the bench. So, we are once again down to the familiar names of Bentil, Hunter and Young for the last spot. Bentil is almost assuredly third in line at this point. He’s behind all the other bigs on the roster and needs more seasoning. He’s probably heading for Maine as well.

This leaves us with the long-covered Hunter vs Young debate. Danny Ainge has said he would like to make a trade to free up a roster spot. Teams are loath to give up on a first-round pick prior to the end of their contract, and the Celtics are no exception. Expect Boston to keep working the phone up until the roster deadline (which is Monday, 10/24) to try and clear a player or two. If not, we’ll see who has done enough to make the club out of Hunter and Young. It is almost personal preference at this point for fans.

Rookie Scale Extension

This one is pretty cut and dry. Only Kelly Olynyk is eligible for an extension of the Celtics’ current players. He’s eligible for a salary up to the maximum for a player with his years of service, which is expected to be approximately $24 million. He’s also eligible for a maximum of 7.5% raises off that first year salary as well. We all know Olynyk isn’t getting anything approaching a maximum contract, but his situation is still interesting nonetheless.

He’s a true stretch 4 who can also function as a stretch 5. With shooting at a premium around the league, especially from bigs, Olynyk is likely to see a first-year salary north of $10 million. Where does this leave Boston? Should they work out an extension or let him hit the market as a restricted free agent?

Olynyk’s cap hold (the placeholder amount until he is signed) is just $7.7 million. Given that this is at least $2 million or so less (and possibly a lot less) than what he’s probably signing for, it is best for Boston to let Olynyk reach free agency. They can conserve valuable cap space to make other moves and then sign Olynyk later in the summer. This is the approach the Celtics have used the past two offseasons with Tyler Zeller and Jae Crowder. Do your other work first while the small cap hold is on the books, and then re-sign your player.

If another team makes Olynyk an offer, it could force Boston’s hand. But as a restricted free agent, the Celtics have the right to match any offer Olynyk gets. Given Danny Ainge’s affinity for Olynyk and his skill set, it is highly likely Boston will have him back in the fold one way or another.

Team Options for Rookie Scale Players

The Celtics have four players on Rookie Scale contracts: R.J. Hunter, Terry Rozier, Marcus Smart and James Young. By the end of October, the Celtics must decide if they intend to exercise their Team Options for 2017-18 for each player. Team Options on Rookie Scale contracts must be exercised a year in advance.

At this point it is a virtual lock that Smart and Rozier will have their options picked up. It looks like it won’t matter for one out of Young and Hunter, as they may not be on the roster after cuts happen next Monday. It is likely that the remaining player will have his option also exercised. Teams rarely choose to decline an option. If a player is a late bloomer, it removes the opportunity to have cheap talent under contract. And once an option is declined, that player is an unrestricted free agent and able to go wherever he chooses.

D-League Assignments

The Celtics are fortunate to be one of the 22 NBA teams that have their own D-League franchise. They’ve made great use of the Maine Red Claws in the past by providing game action for young players who aren’t seeing time in the NBA. By having a franchise that is also close by, the Celtics are able to shuttle players back and forth throughout the season. This allows those players to practice with the Celtics while also playing in D-League games to get valuable on court experience.

NBA teams can assign players on their roster to the D-League who have zero to two years of experience. They can also assign players with three or more years of experience if the player agrees. Currently the Celtics eligible for a D-League assignment without agreement are: Jaylen Brown, R.J. Hunter, Demetrius Jackson, Jordan Mickey, Terry Rozier, Marcus Smart and James Young. Of that group, you can expect to see Jackson and Mickey in the D-League, as well as whoever is kept from Hunter and Young. Those players need reps, and Maine is the best place to get them.

You might notice that Ben Bentil, Marcus Georges-Hunt, Jalen Jones and Damion Lee weren’t included in the above group. As rookies, they are all eligible to be assigned to the D-League. But as likely roster cuts, the process works differently for them.

Each NBA team is allowed four Affiliate Players. An Affiliate Player is a player who attended training camp with an NBA team and was subsequently cut. This is where Bentil, Georges-Hunt, Jones and Lee are likely to find themselves. Should each of them choose to sign with the D-League (players sign a contract with the D-league itself and not individual teams), they are eligible to be assigned to Maine as Affiliate Players.

Given that D-League salaries are still quite low in comparison to what players can make overseas, many NBA teams have started giving out guaranteed amounts for attending camp to likely Affiliate Players. Boston gave Georges-Hunt and Jones $25k each, Lee $50k and Bentil a large guarantee of $250k. For Georges-Hunt, Jones and Lee, this could be a bonus to have attended camp with the Celtics and then to get them to Maine. For Bentil, that large of a guaranteed amount is almost a lock that Boston intends to have him in Maine. It is likely that the conversation started with the Celtics liking Bentil as a prospect but understanding the lack of roster spots this year. Thus, the Celtics gave Bentil some incentive to stay close by in Maine and in their system, despite not actually being a part of the NBA club.

The challenge with the D-League is that any player on a D-League team (outside of those assigned directly from the NBA club) is a free agent in terms of the NBA. This means that the Celtics could be making a hefty investment in these four players (including the guaranteed amounts for each that hit the Boston salary cap) and could end up losing the players to another NBA team at any time. This is a risk that teams take to try and keep talented players in their system. For a team like Boston, this is a byproduct of having a deep roster and so many draft picks over the last few years.

It is important to note that this process does not apply to Abdel Nader, who Boston drafted in the second round and then watched flourish at Summer League. Nader is reportedly signing a contract with the D-League, and Boston will look to acquire his D-League rights to have him play in Maine. His Draft Rights are retained by the Celtics for as long as he plays professional basketball outside the NBA. He can’t sign with anyone but Boston, unless the Celtics renounce his rights or sign him to an NBA contract and later release him. This sort of complicated situation with the D-League is something that the NBA and NBPA would like to solve. Progress has been made on D-League reform and two-way contracts (where players are paid one amount while in the NBA and another while in the D-League), but we’ll have to wait for the new CBA to know for sure.