So when he got the news Thursday he said his farewells. "I was able to say goodbye to everybody, " Mack said. "That was a good place to leave it. Not a bad ending or nothing."
But then he started looking toward the future.
"It will give me new life and new opportunity, " Mack said.
On Sunday, Mack made the most of that opportunity, scoring a season-high 16 points and dishing out six assists.
Mack will have every chance to compete for minutes with rookie Raul Neto and third-year guard Trey Burke. Mack's size and physicality could make him a go-to choice when it comes time to defend against the NBA's bigger and stronger point guards.
"What we're looking for more than anything is consistency from that position, " Jazz coach Quin Snyder said. "… We traded for him to help us and he is different than the other guys. He is going to play and how much or how little is going to depend on a lot of other things, including him, including other players, including who we're playing against. You know, when Jrue Holiday is backing us down, that's a better matchup for Shelvin than it is for Raul and Trey."
Mack and Jazz forward Gordon Hayward know each other from their time playing together collegiately at Butler. But it's Mack's relationship with Snyder, a former assistant in Atlanta, that could pay off big as he enters this new situation.
"He helped me a lot, especially with the pick and roll, " Mack said. "That was the year I played the most in Atlanta. He helped me with my footwork, breaking down the game, just seeing different things. The work we did helped me out a lot with my career. It's an easy transition coming here."