Matthew Macklin believes Katie Taylor is "one of the most exciting fighters in the world" after watching the Irish star unify world titles in Brooklyn.
Macklin was full of praise after the classy showing, saying: "Taylor's story is a special one, she's a special talent.
"In both men's and women's boxing, she is one of the most exciting fighters in the world.
"Her timing and distance was exquisite and she was bouncing on her toes all night long. She's an excellently conditioned athlete and never looks tired.
"She controlled it behind the jab, slipping and countering brilliantly and got well ahead on the cards.
"Bustos - who can hold her head high because she was simply beaten by the superior boxer - came out firing in the eighth and Katie engaged. She obliged and sat in the pocket to fight fire with fire, shipping shots as well.
"That's what makes her exciting. With 20 seconds to go, having won every round up to then, she stands toe to toe and trades, you wouldn't normally see that.
"She's a sporting icon, that's what she is in Ireland, every single person knows who she is, and she is a household name. Now, after just 18 months in the pro ranks, she has unified the division."