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The "Total Bellas" stars stop by "The Tonight Show" to promote WWE's groundbreaking, all-female pay-per-view event, Evolution.

Nikki and Brie Bella played dress up with Jimmy Fallon on "The Tonight Show" Friday night before facing off in mini-wrestling wring for a thumb war.

"Come play with us, Jimmy," the famous twins taunted the NBC late-night hosts while dressed like those creepy identical twin girl ghosts from "The Shining."

Of course, Fallon was down, and they really did play. Turns out ghosts love beer pong!

At the end of their interview with the comedian, he challenged them to another little game.

"Nikki, on Sunday night, you're competing for the Raw Women's Championship at WWE Evolution," Jimmy Fallon said. "Tonight though there's another championship belt going up for grabs...this is The Tonight Show Thumb Wrestling Championship belt."

"It matches my dress!" Nikki said. "I better win."

"I will be the referee and I'll have the belt," Fallon said. "I want a fair fight, okay?... Don't cheat."

The NBC late-night host began with the official thumb wrestling countdown -- "1,2,3,4 I declare a thumb war!" -- and the sisters were off.

Nikki and Brie have been part of WWE for over a decade, but this Sunday Nikki will be participating in groundbreaking pay-per-view event, Evolution, which consists of all-female matches. Nikki will be facing off against undefeated Ronda Rousey. The "Total Bellas" stars spoke to Fallon about the "huge" competition and what it means for women in wrestling.

"The fact that I'm going to be there and competing against Ronda Rousey and having my twin sister next to me, I mean it's a dream come true," Nikki said. "It really is."

"It's kind of one of those feelings that the impossible became possible," Brie added. "The women at WWE never thought this day would come and that fact that it's here. It's just, it's a huge honor. It makes us all emotional."

Nikki went on to explain how she's been "training like an Olympic athlete" in preparation for her match with Rousey.

"I'm going for it," Nikki said.

"I've seen you on a bad day, I think you can handle her," Brie said to her sister. "After this Sunday I think [Ronda] will be 24 and 1."

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