Chris Weidman Injured, Title Fight vs. Lyoto Machida Moved to UFC 175 in July

UFC middleweight champion Chris Weidman will undergo minor knee surgery after suffering an injury during training. Consequently, his scheduled UFC 173 title defense against Lyoto Machida has been moved to UFC 175 on July 5 in Las Vegas. 

The UFC made the announcement via its official website Monday morning. The promotion also said it will reveal a new main event for UFC 173, scheduled for May 24 in Las Vegas, in the coming days.

Sources close to the promotion recently told Bleacher Report that the planned main event for UFC 175 was a rematch between featherweight champion Jose Aldo and top contender Chad Mendes. With Weidman vs. Machida moving to UFC 175, however, it appears Aldo-Mendes will be moved to another date.

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Weidman vs. Machida will now headline the UFC's third annual International Fight Week. The following day, BJ Penn will make his featherweight debut against Frankie Edgar in The Ultimate Fighter 19 finale, also held in Vegas. It is the first time in UFC history that cards will be held on consecutive days in the same city.

Weidman was originally scheduled to face Vitor Belfort, but Belfort pulled out of the fight when Nevada banned the usage of testosterone replacement therapy (TRT). The middleweight No. 1 contender posted a statement from his doctor on Instagram (h/t MMA Fighting's Guilherme Cruz) claiming he needed time for his body to adjust to the absence of the synthetic testosterone.

Weidman won the championship last July by knocking out longtime pound-for-pound kingpin Anderson Silva, then defended the belt against Silva in a December rematch. He won that fight when he checked a leg kick from Silva that resulted in the Brazilian breaking his leg in a gruesome scene.

Machida, a former light heavyweight champion, is currently 2-0 at middleweight, with wins over Mark Munoz and Gegard Mousasi.