Well, he was undefeated at that weight, but he was very young and still growing, and never won a world title at that weight. Barrera really made his mark at 122 and above.
He was very good. I was at his first U.S. fight, days after his 18th birthday. He beat some good fighters at 115 and 118, Eddie Cook among them, but he couldn't get a title shot and contemplated giving up boxing for law school. He used to box a lot back then, as he did later in his career.