Undefeated Prospect Holly Holm Injured, Will Not Fight at UFC 181

Undefeated women's bantamweight prospect (7-0) Holly Holm has suffered an undisclosed training injury and will not be able to fight Raquel Pennington December 6 at UFC 181. 

Brazilian media outlet MMA by Neko first reported (as translated by LowKickMMA) the news, and Bleacher Report has subsequently confirmed with Doris Robinson of Holm's management that Holm has withdrawn from her scheduled UFC debut: 

Holm, the inaugural Legacy Fighting Championships Women's Bantamweight champion, was a three-division titleholder in boxing before making her MMA debut in March 2011. 

While her grappling skills remain untested inside the cage, many pundits give Holm a fair chance against UFC women's bantamweight champ Ronda Rousey due to her impressive striking pedigree. 

Holm signed a five-fight deal with the UFC back in July, per MMA Junkie, while it was announced last month that her first fight with the company would be against Pennington, per FOX Sports. 

According to the UFC's official rankings, Holm is the No. 15 women's bantamweight in the world. 

Due to an obvious discord between UFC President Dana White and Holm's manager, Lenny Fresquez, it appeared that the UFC may pass on signing Holm as recently as March, per UFC Tonight (via Yahoo! Sports). 

Pennington has lost three of her past four contests and is just 4-4 overall as a professional mixed martial artist. 

Her last bout was a close split-decision loss to Jessica Andrade at UFC 171 in March. 

The UFC is yet to formally comment on Holm's injury so there is no word on if a replacement will step up to the plate to fight Pennington on less than one month's notice. 

UFC 181 takes place at the Mandalay Bay Events Center in Las Vegas, Nevada, and it is headlined by a welterweight championship fight between Johny Hendricks and Robbie Lawler. 

John Heinis is a featured columnist for Bleacher Report. He is also the MMA editor for eDraft.com.