If you can believe it, Jaylen Brown is already entering the final year of his rookie deal with the Boston Celtics. You're not the only one if you're thinking it feels like just yesterday that the Celtics drafted him.

But, here we are, heading into the 2019-20 NBA campaign, and Brown is up for a contract extension ahead of the Oct. 21 deadline.

Right now, it doesn't appear that the Celtics and Brown will be getting anything done. There has not been any chatter about the two sides negotiating a deal, so the chances of one coming to fruition over the next month seem slim.

And that fits right with Boston's modus operandi.

The Celtics are not known to hand out contract extensions to guys on rookie deals. They didn't do it for Terry Rozier. They didn't do it for Marcus Smart. They won't do it for Brown.

As a matter of fact, that fact that the Celtics allowed Smart to get to restricted free agency (which resulted in Boston re-signing him on a four-year, $52 million deal) is concrete evidence that Boston won't be extending Brown.

The Celtics highly value what Smart brings to the table, and while Brown may be the more talented guy in terms of raw skill, Smart has actually been the better player thus far and has been more valuable to his team.

When you add everything up, it doesn't seem like the Celtics will be giving Brown an extension, and that is the right move.

Don't get me wrong: Brown is a good player. He plays both ends of the floor, he's athletic, he can shoot and there are times when he takes over games. But consistency is a big thing, and Brown has not shown that yet.

To be fair, he turns just 23 years old next month, so it's not like Brown can't still improve. He can, and he will. But he hasn't shown enough thus far to warrant Boston doing something for him that it hasn't really done for anyone else.

Brown averaged 13.0 points and 4.2 rebounds over 25.9 minutes per game this past season, shooting 46.5 percent from the floor, 34.4 percent from 3-point range and 65.8 percent from the free-throw line.

It should be noted that his numbers were a bit skewed, as he had a nightmarish first month and a half that took him time to climb out of. From December on, Brown actually played pretty well. Not great, but well.

The biggest issues with Brown (other than his consistency) are his lack of a go-to move and his poor free-throw shooting.

Someone as athletic as Brown should be beating defenders regularly, and his free-throw rate should reflect that. He should be getting to the charity stripe more than just 2.7 times per game.

Brown often seems to get caught in between when he has the ball in his hands, and his indecisiveness often leads to bad shots. He doesn't turn the ball over a whole lot, which is great, but sometimes, ill-advised shot attempts are just as crippling as turnovers.

And when he does get to the foul line? He doesn't convert. There is no reason why a shooting guard should be making under 70 percent of his free throws, especially when said shooting guard is a solid 3-point shooter. That is inexcusable, and it's something Brown needs to work on.

In addition, Brown's basketball IQ is questionable at times, and his tendency to ruin offensive sets by not being in the right place at the right time has drawn the ire of Smart on numerous occasions.

These are all reasons why the Celtics should not extend Brown.

Of course, Brown could have a huge year with an increased role, which could set him up for a max contract in free agency next summer. But if that happens, it happens, and Boston can adjust accordingly.

But right now, Brown is not deserving of an extension from an organization that simply does not hand extensions out.