IMPERIAL, Calif. — Andy Ruiz Jr. is chubby, there’s no getting around that.

He has been called a “fat slob,” the “Pillsbury Doughboy” or, more charitably, a “lunch-pail guy.” He’s been compared, by a former trainer no less, to the cherubic and overweight boy Russell from the movie “Up.” His prefight ritual of scarfing down Snickers bars has only fed this image.

But now there is a new nickname, one his father shouted from the audience recently at the Jimmy Kimmel show in Los Angeles as the younger Andy Ruiz sat in the spotlight: “Rocky Mexicano.”

The 29-year-old son of Mexican immigrants, Ruiz became the unlikely heavyweight boxing champion on June 1 by pummeling and repeatedly knocking down Anthony Joshua, the chiseled, unbeaten British champion making his American debut at Madison Square Garden in an air of preordained victory and on a mission to restore the glory of the heavyweight division.

Since then, fame and riches have come quickly for the paunchy kid with the killer punch from the border town of Imperial.