World ranked welterweight Giovani Santillan (23-0, 13 KOs) weighed in successfully at 146.3 lbs., but challenger Alejandro Barboza (11-1, 7 KOs) failed to make the welterweight limit by coming in at 147.8 lbs.
As a result, Santillan will retain his WBO NABO title with a win. Should he lose, the title will become vacant. By not making weight, Barboza is ineligible to win the championship should he upset Santillan.
Santillan vs. Barboza is the "Locked n' Loaded" main event taking place this Friday, April 27.
The 10-round bout originates from the Doubletree Hotel in Ontario, Calif.
Santillan, 26, is ranked No. 5 by the WBO and last defended his title in November against Dodzi Kemeh in what was a one-sided affair that ended in a fourth round knockout win for Santillan.
The southpaw from San Diego initially won the belt last summer when he traveled to Sammy Valentin's hometown of Tampa, Fla. and erased his night by second round stoppage. It will be Santillan's third fight at welterweight.
Giovani Santillan, 146.3 lbs. vs. Alejandro Barboza, 147.8 lbs. (10-rounds)
Saul Sanchez, 117.7 lbs. vs. Sam Rodriguez, 117.5 lbs. (6-rounds)
Miguel Alcantara, 121.9 lbs. vs. Jose Fabian Naranjo, 121.7 lbs. (4-rounds)
George Acosta, 134.7 lbs. vs. Bryan Santiago Tovar, 133.2 lbs. (4-rounds)
Jonah Flores, 121.9 lbs. vs. Neri Garcia, 121.8 lbs. (4-rounds)
Luis Lopez, 149.7 lbs. vs. Maurice Scott, 142.7 lbs. (4-rounds)
Tickets for "Locked n' Loaded" are priced at $40, $60, & $100 and are available for purchase on the day of the event (Friday) at the will call booth starting at 5:30 p.m. local time from the Doubletree Hotel in Ontario, Calif.