'A flawless showing': UFC knockout Mackenzie Dern DANCES in the octagon after another stunning submission win (VIDEO)

Mackenzie Dern couldn't contain her delight in the cage after she stunned Randa Markos with a first-round submission in Las Vegas on Saturday, with the American celebrating her win - and a performance bonus - with an octagon jig.

After claiming a history-making kneebar victory in her previous outing against Hannah Cifers in May, Dern focused on another limb entirely as she applied a tight armbar to Markos in the first round of their contest inside the UFC Apex, forcing the tap and giving Dern the sixth submission win of her career.

The fight was contested on the feet in the opening exchanges but the tide turned midway through the round when Dern slipped to the canvas while attempting a kick. Markos – who has sworn to the media that she wouldn't initiate grappling exchanges with submission specialist Dern – broke her own rule and followed the Brazilian Jiu-Jitsu expert to the mat.

However, it didn't go according to plan. Markos soon found herself fighting off an array of submission attempts from the grappling queen. Dern first threatened with a triangle choke before working towards mount.

It was from this position that Dern began to apply the fight-finishing technique, methodically working her way to Markos' arm before pulling back to the mat with the armbar attempt. The tap came soon after. 

"I’m so happy," Dern said after the fight. "I really wanted to show my hands a little more. I don’t know why the girls want to stay on the ground with me. I got a submission, representing jiu-jitsu."

Dern has now won two straight fights since suffering the first defeat of her career against Amanda Ribas last October, with the 27-year-old now poised to make an assault on the UFC's strawweight fold – and one expects that she will be more than a handful to the 115lbs elite.