Phoenix Suns center Jermaine O'Neal and general manager Lance Blanks engaged in a blistering, expletive-laced confrontation in the coach's office on Monday, league sources told Yahoo! Sports.

"It was really bad," one Suns source said Tuesday afternoon.

The confrontation happened after interim coach Lindsey Hunter's first practice and unfolded within earshot of several Suns players in the locker room, sources said.

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O'Neal is frustrated with the direction of the Suns' rebuild and wanted more clarity on his future this season, a source with knowledge of the confrontation said. At 13-28, the Suns have the worst record in the Western Conference.

O'Neal signed a one-year deal in the offseason with Phoenix.

The Arizona Republic reported Tuesday that O'Neal missed practice with an "unstated medical issue" and wouldn't make the team's trip to Sacramento.

Blanks didn't immediately respond to a text message.