1. Rajon Rondo
The Mavericks have taken gambles and made regrettable moves. Such is life as an NBA franchise, but none turned into a larger disaster than trading for Rondo in December of 2014. The Mavs were sixth in the Western Conference at 19-8 and hoping to jump into title contention when the move was made.
Rondo was a four-time All-Star and the Celtics starting point guard during their 2008 title run. He had playoff experience and was an upgrade over Jameer Nelson. Dallas had the top offensive rating in the NBA at the time of the trade but needed to improve their defense. Rondo’s ball-dominant style made the offense take a step back and their D only made a small step forward.
Things unraveled completely in the playoffs. Rondo was benched after ten minutes of action in Game 2 and left the team. The Rockets outscored the Mavericks by 36 points with him on the floor in the first two games, and the point guard was clashing with head coach Rick Carlisle. Rondo did not receive a playoff share after Dallas was bounced in the first round.
Rajon Rondo left for Sacramento in free agency in the 2015 offseason. Dallas gave up three role players and two draft picks to acquire him, but it blew up in their faces. Rondo went on to have a lengthy NBA career, but his time in Dallas was a disaster. The Mavs certainly wish they had never taken the gamble on the four-time All-Star or any of these regrettable pickups.