He wasn't bad...he was good enough to hold a portion of Foster's title that they screwed him out of..and this did Rondon more harm than good eventually...Foster despised him and Rondon was terrified...just terrified of Foster.
The man made four defenses in one year, when the other co-champion of the division was Bob Foster.That's pretty damn impressive, even for now.
It was said in those days that Rondon had a drinking problem which ultimately led to an untimely death. Don't know if this impacted in his fights - perhaps he did not appear in those bouts at 100% and maybe that's why he lost some of them.
Rondon wasnt anything special. He had those four defenses in 71 but Del Papa was awful, his "title" winning victory was thought to be tainted by the idea that his opponent was poisoned, and later when he beat Baird and Brennan he was beating puffed up mediocre middleweights who were past their best.
funny thing about Rondon was that he had some decent wins, as a middleweight he was KO'd by Bennie Briscoe and Jose Gonzalez as a light heavy he beat Jose Luis Garcia (who KO'd Ken Norton) he beat Avenamar Peralta,Roger Rouse,stopped Jimmy Dupree but then was flattened by Bob Foster then Ron Lyle...but he went the full distance with Earnie Shavers in his next fight