Donald Cerrone (16-3 MMA, 3-0 UFC) has stepped in for Sam Stout (17-6-1 MMA, 6-5 UFC) and now meets Dennis Siver (19-7 MMA, 8-4 UFC) at October's UFC 137 event.

As MMAjunkie.com (www.mmajunkie.com) first reported earlier today, Stout recently withdrew from the event for undisclosed reasons. Event sources confirmed the opponent switch.

Fellow lightweight Cerrone now takes his spot on the card and fights for the fourth time in 2011.

UFC 137 takes place Oct. 29 at the Mandalay Bay Events Center in Las Vegas. The night's main card airs on pay-per-view, though it's not clear where Cerrone vs. Siver will be placed in the lineup.

Stout suffered a devastating blow earlier this month with the death of his brother-in-law and longtime trainer, Shawn Tompkins. However, it's not clear if that's the reason for his withdrawal.

His replacement, Cerrone, is flying high after a move over from the now-defunct WEC, where he was a longtime contender. He's since moved into UFC title contention with wins Paul Kelly ("Fight of the Night"), Vagner Rocha and Charles Oliveira ("Knockout of the Night"). He's now won five straight fights, which included WEC victories over ex-champ Jamie Varner and Chris Horodecki.

Siver, meanwhile, is 8-1 over his past nine fights, which includes a 7-1 mark in the octagon. Along the way, he's picked up four "Fight Night" bonuses – two for the evening's best knockout and one each for best submission and best fight.


Source: Donald Cerrone replaces Sam Stout at UFC 137, meets Dennis Siver