Dallas Mavericks head coach Rick Carlisle resigns after 13 seasons

In the team's second major management-team departure of the week, Mavs head coach Rick Carlisle is out.

Carlisle announced his resignation yesterday, one day after the ouster of his long-time friend, general manager Donnie Nelson.

Carlisle gives no specific reason for his decision.

In a tweet, Mark Cuban says: "I truly love Rick Carlisle. He was not only a good coach but also a friend and a confidant. Our relationship was so much more than basketball. And I know that won't ever change."

Carlisle coached the Mavs for 13 seasons and led them to the franchise's only NBA title in 2011.