The Big East’s future became even more uncertain Thursday, when the Big 12 offered Texas Christian University a spot in its conference. TCU had agreed last November to join the Big East.

The TCU Board of Trustees will meet today and is expected to accept the offer. If the Horned Frogs, currently members of the Mountain West Conference, do choose to join the Big 12, they will have to pay a $5 million exit fee to the Big East.

Joining the Big East was always a geographical stretch for the Horned Frogs, and, as a TCU press release noted, joining the Big 12 “will allow [them] to return to old rivalries” with local schools like Texas and Texas Tech.

Should TCU accept the Big 12’s invitation, it may not be the only newcomer to the conference. Missouri is rumored to be pushing for an invitation to the Southeastern Conference and, should the Tigers leave for the SEC, the Big 12 would likely look to replace them. Big East schools Louisville and West Virginia have been rumored as potential targets for the Big 12 if that scenario plays out.

The news about TCU is especially damaging to the Big East in the wake of the defections of Pittsburgh and Syracuse to the Atlantic Coast Conference. In response to those departures the presidents of the 14 remaining Big East schools met at Georgetown last Sunday and authorized Commissioner John Marinatto to pursue the addition of other institutions interested in joining the conference. Navy, Army, Air Force, Temple, Central Florida and SMU were discussed as possible candidates at the meeting, but the Big East has yet to extend any formal invitations to those or other schools.