Mexican boxing legend Julio César Chávez has legally changed his name to Saúl Álvarez Sr following his son's embarrassing defeat to Daniel Jacobs.

Chávez Jr was booed out of the Talking Stick Resort Arena in Phoenix and pelted by his betrayed Mexican fans after quitting on his stool against former middleweight champion Daniel Jacobs before the sixth round.

Unprofessionalism has plagued Chávez Jr's career, and his latest (and possibly last) fight was no different, with him skipping pre-fight drug tests and weighing in a ridiculous 4.7lbs over the 168lb middleweight limit.

But nobody has been embarrassed by his antics over the years more than perhaps the best Mexican fighter of all time, the father who gifted his name to Chávez Jr at birth, Julio César Chávez Sr, who finally decided enough is enough and released a scathing statement explaining his decision:

"The time has come for a change. I can no longer bear the name of this disgrace to boxing. He wouldn't do the right thing and relinquish my name, so earlier today I made the decision to visit the county court in Culiacán and legally change my name to Sául Álvarez Sr.

"My new name is inspired by a real Mexican champion, my real son, Canelo. I discussed it with him before I made the application and he gave me his blessing.

"He might eat questionable meats and create his own weight classes, but he would never quit or miss weight because he was getting high in the basement and eating churros instead of training.

"Never again will I have to walk the streets of Mexico with my head hanging in shame because that lazy disgrace has let my country and me down. F*** you, Julio."