UFC 168 adds Chris Leben vs. Uriah Hall and Dustin Poirier vs. Diego Brandao to Dec. 28 fight card in Las Vegas

Ultimate Fighting Championship (UFC) has announced a pair of compelling mixed martial arts (MMA) fights for its upcoming UFC 168 pay-per-view (PPV) event, which is set to go down inside MGM Grand Garden Arena in Las Vegas, Nevada, on Dec. 28, 2013.

First up is a middleweight bang-o-rama between Uriah Hall vs. Chris Leben.

Hall (7-4), who graduated The Ultimate Fighter (TUF) 17 with the weight of the combat sports world on his shoulders, failed to deliver in two consecutive bouts inside the Octagon. His performances were so baffling, in fact, it prompted UFC President Dana White to declare that Hall wasn't mentally fit to compete.

Then why not pair him off against someone who in the past, hasn't been physically fit to compete?

Leben (22-10) is in the midst of a dreadful 1-4 run, dropping three straight fights since getting finished by Mark Munoz back in late 2011. Like Hall, White was not predicting an extended run inside the Octagon following years of punishment, which he attributes to "The Crippler's" brand of kill-or-be-killed offense.

Someone could be on the chopping block at UFC 168.

On the flip side, someone could be in the title hunt at 145 pounds, depending on how well Poirier (14-3) performs in "Sin City." After a disappointing setback against Cub Swanson earlier this year in London, "The Diamond" was as sharp as ever in his next trip to the cage, turning away former division contender Erik Koch at UFC 164.

He's got his hands full in December.

That's because Brandao (18-8) hasn't tasted defeat since getting tripped up by Darren Elkins in his sophomore appearance. Since then, "DB" has rattled off three in a row, including a unanimous decision win over Daniel Pineda at the UFC Fight Night 26 event last month in Boston.

Get ready for a war.

UFC 168:"Weidman vs. Silva 2" will be headlined by the biggest middleweight title fight in history, as newly-crowned champion Chris Weidman tries to go two-up on former 185-pound kingpin Anderson Silva.

Leave no doubt.

The co-main event will feature UFC Women's Bantamweight Champion Ronda Rousey in a second go-round with former Strikeforce nemesis and fellow TUF 17 coach Miesha Tate.

For more news and notes on UFC 168 be sure to check out our complete event archive right here. To check out the latest "Weidman vs. Silva 2" fight card and rumors click here.