After weeks of speculation, Butler University formerly announced plans Wednesday to leave the Horizon League for the Atlantic 10 Conference in all sports except football and women's golf.

The move will begin with the 2013-14 season.

The Atlantic 10 does not host football or women's golf. Butler's football team will remain in the Pioneer League and the women's golf team will seek a new conference, the school said. 

“Moving to the Atlantic 10 allows us to associate and compete with institutions with outstanding academic profiles and values,” Butler Athletic Director Barry Collier said in a prepared statement. “They value the experience of the student-athlete.”

Butler was a co-founding member of the Horizon League and has been among its most dominant men’s basketball programs, advancing to the NCAA championship game in 2010 and 2011.

Butler and Loyola University have been members of the league since 1979, when it formed as the Midwestern City Conference. It later became the Midwestern Collegiate Conference before taking the Horizon name in 2001.

Butler will not be the only Midwest university in the Atlantic 10. The University of Dayton and Xavier University in Ohio, in addition to Saint Louis University in Missouri, also are members.

Butler's interest in the Atlantic 10 became public in early March.