Joanna Jedrzejczyk to fight Valentina Shevchenko for flyweight title at UFC 231

The UFC will have a new female flyweight champion after UFC 231 on Dec. 8 in Toronto.

Valentina Shevchenko is set to take on former strawweight champion Joanna Jedrzejczyk for the vacant belt, the promotion announced late Thursday night. Nicco Montano held the belt until she had to withdraw from a UFC 228 fight with Shevchenko in early September because of health reasons and was stripped of the title.

Jedrzejczyk (15-2) won the UFC's first strawweight belt back in 2015 and defended it five times before losing to Rose Namajunas at UFC 217 last November. She is 1-1 since, losing the immediate title rematch to Namajunas in April by unanimous decision but defeating Tecia Torres by unanimous decision in July.

Shevchenko (15-3) has fought most of her career at bantamweight. She faced Amanda Nunes for the belt at UFC 215 last September and lost by split decision. She subsequently moved down to her more natural flyweight and finished Priscila Cachoeira by second-round TKO in February.

Jedrzejczyk told ESPN's Ariel Helwani earlier this week she was open to a move up to flyweight.

"I'm always willing to fight, and the UFC knows it," Jedrzejczyk said. "I'm open to move up and fight for the belt with Valentina Shevchenko. If [this fight] is going to happen, it's going to be this year."

Jedrzejczyk has had tough weight cuts in her career, most notably before UFC 217 last November when she surrendered her belt to Namajunas. She admitted to losing 15 pounds in 14 hours to make the 115-pound limit and later fired her nutritionists. The move to flyweight would allow her to be a more natural 125 pounds on fight night.