Despite earlier published reports that Ed Herman had been tapped to replace an injured Yushin Okami at UFC 98, MMAmania.com can now exclusively confirm that former WEC middleweight contender Chael Sonnen will be Dan Miller's new opponent for the "Evans vs. Machida" event on May 23.

"Thunder" was forced to withdraw from the card after tearing a ligament in his knee, joining a long list of fighters who were removed from the UFC 98 lineup due to injury.

Since its inception, the May 23 event has been a revolving door of UFC talent.

Heavyweight stars Frank Mir and Brock Lesnar were originally set to unify the heavyweight title in the main event until Mir opted for surgery on a bothersome knee and forced UFC officials to push their rematch forward to UFC 100.

The Zuffa brass hastily arranged for Quinton Jackson -- fresh off his unanimous decision win over Keith Jardine at UFC 96 -- to challenge light heavyweight champion Rashad Evans as a replacement main event.

"Rampage" felt pressured to fight on such short notice and instead chose to take some much-needed time off to heal an injured jaw and some other nagging injuries before trying his luck against "Sugar."

Enter Lyoto Machida.

With "The Dragon" in place to meet Evans, everything was back on track -- until Josh Koscheck broke his toe and pulled out of his fight against Chris Wilson.

Brock Larson to the rescue.

Earlier today, it was learned that James Irvin blew out his knee and would not be able to throwdown with Drew McFedries in a middleweight scrap. Xavier Foupa-Pokam will assume the position, pending immigration proceedings.

That brings us to Okami. The Japanese import — who holds a controversial win over Anderson Silva under the 'Rumble on the Rock' banner — has won seven of eight fights inside the Octagon. His lone loss during that span was to former champion Rich Franklin back at UFC 72: "Victory" in June 2007.

After defeating Brazilian jiu-jitsu specialist Dean Lister at UFC 92: "The Ultimate 2008″ in Dec. 2008, Okami re-established himself as a top contender in the middleweight division after missing nearly nine months of action due to a hand injury.

This latest setback could further stymie his chances at getting a rematch with Silva -- who may be toiling in the land of light heavyweights indefinitely.

Bad news for Okami, great news for Sonnen, who will attempt to rebound from a quick first round submission loss (triangle choke) to Brazilian jiu-jitsu powerhouse, Demian Maia, at UFC 95 earlier this year.

The bout marked his third UFC appearance – he lost to Jeremy Horn via submission (armbar) at UFC 60: "Hughes vs. Gracie" back in 2006 and outpointed Trevor Prangley on all three judges scorecards at Ultimate Fight Night 4 that same year.

Prior to the loss to Maia, Sonnen handed a dazed and confused Paulo Filho — who was widely regarded as the second-best middleweight fighter in the world before encountering major personal issues — his first career loss at WEC 37 on November 5.

How this affects his planned bout against Wilson Gouveia at UFC 102 in August remains to be seen.

UFC 98 will feature (we hope) the light heavyweight title fight between Rashad Evans and undefeated challenger Lyoto Machida. Also on the May 23 card, former UFC welterweight champions Matt Hughes and Matt Serra will finally settle their eternal grudge match.

For the latest UFC 98 fight card and rumors click here.