Anthony Pettis Withdraws from UFC on Fox 9, Johnson vs. Benavidez New Main Event

Anthony Pettis has withdrawn from his scheduled title defense opposite Josh Thomson at UFC on Fox 9, resulting in a major shakeup over the next two UFC cards, according to Fox Sports.

Word came out over the last few days that the newly-minted UFC lightweight champion suffered a knee injury, but UFC President Dana White, as he so often does, insisted the bout was still going to go down.

Pettis was supposed to fight Thomson, the former Strikeforce lightweight champion who recently knocked out Nate Diaz, in the main event of the Dec. 14 card. 

With the lightweight title fight nixed, the UFC has moved the flyweight title fight between Demetrious Johnson and Joseph Benavidez from The Ultimate Fighter Season 18's Finale to UFC on Fox 9's top billing. Nate Diaz vs. Gray Maynard will be elevated to the main event of the Nov. 30 card, replacing Johnson vs. Benavidez.

"

The #TUFFinale main event on @TUFonFS1 will now be @GrayMaynard vs. @NateDiaz209. They will fight three rounds.

— UFCONFOX (@UFCONFOX) November 11, 2013"

There is no word yet on the severity of Pettis' knee injury, and how long he is expected to be out. As of Saturday, Pettis was in Las Vegas visiting the UFC's preferred doctor for knee injuries, Dr. Steven Sanders. Pettis lives and trains in Wisconsin.

Additionally, it is unknown whether the UFC is committed to keeping Thomson as Pettis' next opponent.

Thomson was originally an injury fill-in for heavy-handed Canadian T.J. Grant, and if the injury keeps him out of the cage for an extended period of time, it could put Thomson into the thick of a crowded upper tier of the division that also sees Gilbert Melendez, Rafael dos Anjos and Khabib Nurmagomedov all clawing toward a title shot.

Dominick Cruz is slated to finally make his return to the Octagon after two years out of action due to knee injuries. Here's hoping Pettis doesn't end up holding up a far-more-stacked lightweight division with a serious knee injury of his own.

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