Dallas Mavericks owner Mark Cuban and former Mavs coach Don Nelson aren’t best friends forever. The AP reports:

The feud between Dallas Mavericks owner Mark Cuban and former coach Don Nelson stretches back nearly seven years and has some $7 million at stake. But just how ugly and dysfunctional their relationship has been is only now being revealed.

Previously secret testimony and e-mail, now in the public record as part of legal proceedings initiated in the last 10 months, paint the picture of a spat that has turned two of the NBA’s best-known figures into bitter adversaries.

There’s deposition testimony from Cuban in which he acknowledges that he withheld consulting fees from Nelson in 2006 because he believed the former coach had “badmouthed” the team during the NBA Finals and should be made to “beg” for the money.

There’s also testimony from Nelson in which he describes being so disgusted with Cuban that he signed a contract to stay on as coach in 2003 only after friends “got me drunk.”

As great as that sounds, there’s more, again from the AP:

Nelson has also filed a defamation suit against Cuban in California over comments the owner made on a Bay Area radio show in 2007. He claims that Cuban, who was on the show to promote his appearance on “Dancing with the Stars,” defamed him when he said the coach’s demand for money was an attempt “to rip me off.”

This goes deep. The two likely will never be able to hug it out and walk it off.