A rising star a couple of years ago, Kanako Watanabe has since grown rapidly and become a core presence on the Japanese national swimming team at the age of 18.

The "Tobiuo Japan" team captured four medals, including three golds, at the FINA world championships, which wrapped up in Kazan, Russia, on Sunday. Half came from Watanabe, who won gold in the 200-meter breaststroke and silver in the 200-meter individual medley.

Just a few years ago, it was hard to foresee her competing at the world's top level. Watanabe made Team Japan for the 2012 London Olympics, which was an accomplishment in itself, but didn't qualify for the 200-meter breaststroke final. At the 2013 world championships in Barcelona, she didn't advance to the finals in the two disciplines she competed in (She didn't even get through the heats in the 100 breaststroke).