I could see Smart available if the Celtics think they need to land top player. Could happen if it doesnt look like they can go where they want to go with what they have. I could see a package with Brown, Smart and other assets. Smart would be used as a salary, thats where the Mavs could in as a 3rd team.
Problem DAL has is no assets.
They were screwed by Lotto luck and had to trade up for Luka, then were screwed again and lost the pick in trade the next year whereas two other teams with he same record moved up.
DAL has never moved UP in a lottery. EVER.
The main reason I hold out hope Smart ends up here is he will be too expensive for BOS at some point soon and they will want him far away from their biggest rivals as well as the Eastern Conference.
He will want to start and DAL could see him as their 2B to KP. So role isn't an issue. Neither is fit as a great 3 and D guard is exactly what you want next to Luka. His added toughness is just icing.
But there really is no deal on the horizon that would make BOS consider it so it'd be at least year from now and have to include some cap relief and some future draft capital.
I think the best now move is Jae Crowder.
He's a former Mav who was well liked here.
He has a limited but very usable game.
Then again MEM has gotten hot and is holding onto the 8 spot so may not wanna part with anyone in the rotation.