On August 4, 2006, Watanabe knocked out the previously undefeated Shinashi with a hard punch to the chin in a rematch to capture the DEEP Women's Lightweight Championship. Shinashi suffered a broken jaw and a cheekbone fracture from the punch and a big cut from her face hitting the canvas. She retains a permanent bruise on her left cheek from Watanabe's knockout punch. Watanabe was defeated by Seo Hee Ham in a non-title bout at DEEP: 28th Impact on February 16, 2007.