Since trading Paul Pierce and Kevin Garnett, the Boston Celtics have tried their best to maintain salary cap flexibility. They have signed free agents to short contracts. They have refused to target good (but not quite good enough) players who would have eaten into long-term cap space. They clearly desire a star and don't want other commitments to ruin their chances.
All of that could make things interesting next summer when Isaiah Thomas and Avery Bradley could both be up for contract renegotiations. The situation is complicated, but I'll try to explain as well as I can.
To be clear: I don't know how much Thomas and Bradley would want in a possible renegotiation, and I don't know how much the Celtics would be willing to give. I don't know how Thomas and Bradley would feel about finishing out their current bargain deals if it meant the team could continue chasing big stars.
I do know three things:
1. Thomas and Bradley both deserve a lot more money. One's an All-Star. The other made the all-defensive team. Both have smaller contracts for next season than Matthew Dellavedova. It's a weird NBA world right now, and most players on old contracts are badly underpaid.
2. The Celtics would love to have maximum cap space next summer when Stephen Curry, Kevin Durant, Russell Westbrook, Blake Griffin and Chris Paul could all hit the market along with players like Gordon Hayward, Kyle Lowry and Paul Millsap.
3. The two previous items on this list clash.
Under the current collective bargaining agreement, players can renegotiate four-year or five-year deals after the third anniversary of a signing. A team must have cap space to offer a raise, and pay cuts are not allowed. Why would a team volunteer to pay a player more money when he's already under contract? Doing so can keep a player happy and set up the table for a contract extension. Guys like Thomas and Bradley have little incentive to extend their current deals because they can only make 107.5 percent in the first year of an extension (with 7.5 percent raises after that), but if they simultaneously renegotiate the deal, that 107.5 percent would look a whole lot more attractive. The Houston Rockets used a similar technique to renegotiate-and-extend James Harden, adding years of team control on his contract in return for more money now. The Oklahoma City Thunder would love to use the same strategy with Russell Westbrook. For the Celtics, things are more complicated.
By the time Thomas (July 12, I believe) and Bradley (July 15, I believe) can even consider renegotiations, it's likely most top free agents will have already decided on their next teams. The Celtics could find another way to use their cap space, then turn to Bradley and Thomas with a message similar to, "Sorry, bros, we can't possibly offer you more money now." It's even possible the players would be completely on board with that option. Sure, they would miss out on a cash grab for one year, but they would be playing for a contender (or close to it) with the overwhelming possibility of a substantial raise in free agency the following summer. That wouldn't be the worst situation ever.
On the other hand, the Celtics could irritate Thomas and/or Bradley -- one year before they hit free agency -- by spending all of the extension money elsewhere. Maybe it's the right risk to take. Boston would still be a tough situation for those guys to leave (great coach, tight locker room, fun system, competitive team), but hostility toward management never helps.