Big 12 commissioner Dan Beebe is out after the conference nearly collapsed for the second time in just over a year.
In a statement, the Big 12 said its board of directors and Beebe reached a "mutual agreement" for Beebe to leave the job immediately.
Former Big Eight commissioner Chuck Neinas will serve as interim commissioner. He was a unanimous selection by Big 12 university presidents on a conference call Thursday.
The Oklahoman reported Tuesday that the University of Oklahoma would commit to staying in the Big 12 only if the conference ousted Beebe and added regulations on ESPN's Longhorn Network.
Texas A&M announced earlier this month it will leave in 2012 to seek membership in the Southeastern Conference. And Texas, Oklahoma, Oklahoma State and Texas Tech were considering a potential move from the Big 12 to the Pac-12 until it announced Tuesday that it would not expand.
"I put all my effort into doing what was best for the Big 12. With great fondness, I wish the Big 12 Conference a long and prosperous future," Beebe said in a statement released by the Big 12.
The 54-year-old Beebe, who was in his fifth year as the leader of the Big 12, became an easy target for schools upset about instability in the league.
Critics portrayed him as constantly being outmaneuvered by other league commissioners who were picking off his teams one by one and as someone beholden to Texas, the Big 12's biggest and wealthiest member.
Last fall, Beebe was granted a three-year extension on his contract through 2015. When the extension was announced, University of Missouri chancellor Brady Deaton, chairman of the league's board of directors, said Beebe had been "an outstanding leader" during challenging times.
Beebe is also a member of the 10-person NCAA tournament selection committee. Beebe is the second person to lose his job while on the committee this year. The current chair, Jeff Hathaway, was forced to retire at Connecticut as athletic director. Hathaway became the chair on Sept. 1. Beebe's five-year term ends in September 2014.
Beebe, a former NCAA enforcement director, was commissioner of the Ohio Valley Conference for 13 years before joining the Big 12 in 2003 as associate commissioner and chief operating officer. Beebe was named Big 12 commissioner in 2007.
Beebe was publicly credited in April with playing a key role in negotiating the Big 12's television deal with Fox Sports that pays the league about $90 million a year. In his tenure, the Big 12 has won 12 national championships in various sports and a record $145 million was sent to its membership in 2010-11 under the revenue-sharing model he helped arrange.
Information from The Associated Press was used in this report.