You might attribute some of his improvement this season to the fact that he is in a contract year, looking to cash in on a big payday while he's still in his prime after getting the short end of the stick because of taking a discount to play with his brother Markieff.
But that would be doing the man a tremendous disservice, as he's been more than willing - downright enthusiastic, actually - to take whatever role was needed for the Boston Celtics to win.
This is the man, after all, who coined the "Bench With Attitude/BWA" moniker - and whose injection into the starting lineup breathed new life into a gasping Celtics offense.
Marcus Morris exits with 31 points, four rebounds and four assists. Heck of a performance.
Once aspersed for his propensity for devolving to ISO ball peppered with long twos, he's transformed his game, moving the rock and hitting from deep a scorching-hot rate of .429 (far above his previous best of .369).
We saw that on full display last night against the New Orleans Pelicans, particular the early second-half sequence when he almost single-handedly buried any hopes the Pels had of crawling back into the game with three consecutive treys in less than two minutes of game time, on his way to a season-high 31-point performance.
We may not be able to afford Mook going forward, so enjoy him while he's here - maybe, if we're really lucky, we can give him a ring as a parting gift.