Leaders of the Big 12 Conference have cleared the way to make Texas Christian University its 10th member.
The league announced the decision Thursday and said the Big 12 board had "authorized negotiations" with TCU.
Missouri did not participate in the vote on the advice of legal counsel.
TCU, the defending Rose Bowl champion in football, agreed earlier this year to leave the Mountain West Conference after this season for the Big East, which has an automatic Bowl Championship Series berth.
But the Big East is on the verge of losing Syracuse and Pittsburgh to the Atlantic Coast Conference. TCU Chancellor Victor Boschini Jr. said the Big 12 discussions "have huge implications for TCU" and would allow the school "to return to old rivalries."
The Big 12 lost Nebraska (Big Ten) and Colorado (Pac-12) over the summer and will lose Texas A&M to the South Eastern Conference next year. Missouri is also exploring options to leave the Big 12.