Watch: Gadelha submits Kowalkiewicz in 1st round with rear-naked choke

Claudia Gadelha isn't giving up her spot at the top of the strawweight rankings anytime soon.

The division's No. 1 contender made short work of fellow 115-pound standout Karolina Kowalkiewicz, submitting her with a rear-naked choke at the 3:03 mark of Round 1 in the co-main event of UFC 212 in Rio de Janeiro on Saturday.

In a battle between the two best strawweights in the world not named Joanna Jedrzejczyk, it was Gadelha who was quicker to the punch both on the feet and on the ground. After scoring a takedown, "Claudinha" immediately transitioned to Kowalkiewicz's back and hunted for a submission. Within seconds, Kowalkiewcz was left with no choice but to tap out or go to sleep.

It was the first time in Kowalkiewicz's career that she lost by knockout or submission. She has now lost two straight fights following a failed bid to dethrone Jedrzejczyk last November. Her professional record sits at 10-2.

Gadelha has won two straight and three of four. The 28-year-old Brazilian attributed her spectacular performance to a change in training camps. This was Gadelha's first finish since July 2013, one fight before she debuted in the Octagon.

In six UFC appearances, Gadelha is 4-2, with her only two losses coming at the hands of Jedrzejczyk.