Weigh in event for Julio Cesar Chavez Jr. vs Sergio Martinez took place on (Fri., Sept. 14, 2012) from the Encore Theater inside the Wynn Hotel & Casino in Las Vegas, Nevada.
160 lbs.: Julio Cesar Chavez Jr. (158) vs. Sergio Martinez (159)
130 lbs.: Miguel Beltran Jr. (131) vs. Roman Martinez (129)
160 lbs.: Joachim Alcine (158) vs. Matthew Macklin (160.5)
122 lbs.: Roberto Marroquin (122) vs. Guillermo Rigondeaux (122)
175 lbs.: Paul Harness (173.25) vs. Mike Lee (174)
154 lbs.: John Jackson (152) vs. Willie Nelson (153.25)
147 lbs.: Daniel Sostre (145) vs. Wale Omotoso (147.5)

