He's not as good as Jeff Green yet. It's something to aim for. Green played 3 years of College ball and was likely further along than Jaylen as a rookie.
I assume Jaylen is going to struggle in a big way as a rookie. I hope he can do enough to stay in the big league, though. He'll learn more playing with these guys than he will spending a season in D-League.
I'm not so sure about that Lar. While Green was considerably more polished but I think Brown is actually better now than Green was coming out of school.
Green averaged 17/8/4 his junior year per 40. Brown averaged 21/8/4 his freshman year per 40. No doubt Green had a significantly better shooting percentage but I think Brown is simply a equal or better player on the offensive end and I was quite impressed with his defense during SL as well. I'm not sure that Brown will get 30 minutes per game as Green did in Seattle his first year but I wouldn't be surprised if Brown was around Green's 10/5/1.5 numbers that Green posted his first year.
I wrote up a long post on why Brown found an ideal landing spot in Boston earlier. One of the points was that Brown offers something to our second unit that is sorely needed with the loss of Turner - he can put the ball on the floor and drive to the hoop. I think he'll have plenty of opportunity to do that and while I expect him to struggle (almost every rookie does), I think there's a ready made out spot that will fit his natural talents while allowing him to adjust to the pro game. I also have the confidence in Brad to make that happen.
Of course everything is predicated upon his performance at the defensive end but I think we might be pleasantly surprised how quickly and how much Brown contributes to this team.