The Joffrey Ballet will flex its muscles as one of the world’s most illustrious dance companies when it performs this weekend at the University of Missouri–St. Louis. The performances, presented by Dance St. Louis and Wells Fargo Advisors will begin at 8 p.m. March 9 and 2 and 8 p.m. March 10 in the Blanche M. Touhill Performing Arts Center at UMSL.