He may have been a Latino ring star brought in or merely some wrestler on the lineup donning a mask and doing double duty. With the passing of time, no one seems sure. In the early 1950s, El Capitan or The Captain as it translates, showed up in Arizona, lasted a while and left as silently as he came.
He appeared in Tucson, Phoenix, Casa Grande, Globe, Mesa and across the border in Nogales, Mexico, usually losing or being used as what the modern WWE would call "enhancement talent" to lose and make the other wretslers look stronger.
Bill Williamson, The Blue Terror, Mike London and Monte Ladue. Since he usually appeared on the undercard this leads to suspicion he may have been someone just donning a mask, passing off as Hispanic and doing the fore-noted double duty.
There seems to be no account of him ever winning a match in Arizona. .