The 185-pound contest will pit two finishers against on another. Leben holds only one decision win in his last seven victories while Vemola has not gone the distance in any of his wins.
The bout was announced Wednesday evening by the UFC Australia Twitter account.
Leben (22-8) tested positive for oxycodone and oxymorphone following his loss to Mark Munoz at UFC 138. As a result of the positive test, Leben was be suspended from competing in MMA for one year. Prior to the Munoz fight, Leben earned the most significant victory of his 30-fight career when he knocked out MMA legend Wanderlei Silva in 27-seconds. The 32-year-old has won four of his last six bouts and will be eager to get his name back in the win column at UFC 155.
Vemola (9-3) is coming off a disappointing defeat to surging middleweight Francis Carmont at UFC on FUEL TV 4 in July. The product of the Czech Republic made his UFC debut as a heavyweight back in 2010 and has slowly worked his way down to the middleweight division. Vemola is 1-1 at 185-pounds and has alternated wins and losses in his past six bouts. The 27-year-old will be looking to start a win streak at UFC 155 at Leben’s expense.
While the Dec. 29 UFC event has yet to be formally announced by the organization, a heavyweight championship bout between Junior dos Santos and Cain Velasquez is expected to headline the event.
A location for the event is unknown at this time. However, in recent years the New Year’s weekend UFC fight card have taken place at the MGM Grand Garden Arena in Las Vegas, Nevada.