China and Spain claimed the first gold medals of the Olympic taekwondo competition on Wednesday.
Wu Jingyu of China defended her Olympic title in the women's 48kg division by beating Brigitte Yague of Spain 8-1 in a fast-paced final she dominated from the start.
Wu was nearly always on the attack, using her flexibility to kick Yague repeatedly from close range.
In the men's 58kg category, Joel Gonzalez defeated Lee Dae-hoon of South Korea by a score of 17-8 to win his first Olympic title.
Two-time world champion Wu was in top form on Wednesday, winning three of her matches so decisively they were ended early after she racked up at least a 12-point lead on her rivals.
Taekwondo fights are automatically stopped if one fighter is 12 points ahead because the gap is considered too big to close.
After losing 14-0 to Wu in the quarterfinal, Japan's Erika Kasahara said there wasn't much she - or anyone else - could do to stop Wu on Wednesday.
"She was just too strong," Kasahara said.
The bronze medals in the women's 48kg division were won by Thailand's Chanatip Sonkham and Croatia's Lucija Zaninovic.
In the men's tournament, world No. 1 Gonzalez beat Lee by blocking his attacks and hitting the South Korean with head shots on the counter.
Gonzalez, 22, is a double world champion and fought aggressively in most of his matches, often using his front leg for targeted attacks on his opponents.
"I did what I know how to do," he said.
"I feel amazing," he said.
The bronze medals were won by Alexey Denisenko and Colombia's Oscar Munoz Oviedo.