9. Antwan Jamison
The Mavs were fresh off a trip to the conference finals in 2003 when they acquired Jamison in a nine-player deal with the Warriors that sent Avery Johnson, Nick Van Exel, and Popeye Jones to Golden State. He was a starter for the Dubs but came off the bench in Dallas behind Michael Finley and Antoine Walker. The 6’8 forward averaged 14.8 points, 6.3 rebounds, and 1.0 steals in 29.0 minutes per game as he won Sixth Man of the Year in 2004.
Jamison’s time with the Mavericks lasted less than one calendar year as he was traded to Washington for Jerry Stackhouse, Christian Laettner, and the fifth overall draft pick, which turned into Devin Harris.
He was in the middle of his prime and immediately became an All-Star with the Wizards. Jamison averaged 20.8 points per game over the next five seasons combined as he made two All-Star appearances and was one of the league’s best forwards. He was a productive role player into his mid-30s and played 16 years in the league.
The Dallas Mavericks did not have a massive role for Antwan Jamison, but they traded him too soon. He was just entering his prime, and the franchise did not get equal production in return.