If you want a solid breakdown of some of the ways that could still happen, and a general overview of the cap situation, check out Dangercart's recent article on the topic. Right now, however, I thought it'd be wise to think of some of the options available to Boston to use its remaining cap space on.
The team is over the cap and currently just under the tax if they used a full mid-level exception, set at $8.6 million this season for non-taxpaying teams, so this was probably planned for when setting the rates for the deals which fell into place ahead of Smart's restricted free agency.
So who are the remaining free agents who could fill some of the needs Boston would have in the backcourt and on the wing should Smart actually secure a deal Boston won't match?
Even just weeks ago, I'd laugh this one off, and not just because of how IT left Boston. I'm still not convinced it'd be a good idea in terms of chemistry, but Isaiah has healed enough now that he might be better than the diminished version of himself we saw last season. He's far from ideal, but the potential for a good narrative is present, and Thomas' scoring would be perfect for a sixth-man role, though Isaiah has chafed at such a situation in the past.
Dude can shoot, full stop. I could keep going about that, but you either know the guy is a lethal sharpshooter who could thrive under Brad Stevens, or you've never heard of the guy. He's not especially flashy, and pretty bad on defense, but as a second-unit option with his offensive talents, that's forgivable.
Crazy that Wayne Ellington remains a FA. If your team needs shooting (read: All 30 teams), Ellington should be high up on the list of priorities. Has sustained his excellent shooting over two consecutive seasons (while taking incredibly difficult attempts) pic.twitter.com/ocph1SMi0A
An older version of Wayne Ellington, though he used to score (and shoot) better, he's also a bad defender. Likely attainable on a veteran's minimum or close to it, too. One shouldn't expect too much from the perennial "Sixth Man of the Year" candidate, but he's likely got enough left in the tank to make a meaningful contribution.
The former UConn standout has carved out a niche for himself since being stood up by LeBron James in Miami, as an efficient scorer and sharpshooter who rarely turns the ball over while also being one of the league's better defenders, a surprise given he's only 6'2 in shoes. A victim of the same cap crunch Smart is, he might just be a more balanced option, even if he's nowhere near as good a defender as Marcus.
You know who's a free agent point guard who is not 85 years old and could have been (and perhaps still will be) had for a bargain?