Claudio Puelles was going to face Sage Northcutt at UFC 214 to be held on July 29 in the United States.
Standardize the HTML code of this article, using divs, paragraphs, and headings; and removing unnecessary CSS or Javascript code. Also, translate the texts that are part of the article into English. Output the result in HTML without any other text:
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Athlete Claudio Puelles injured during training
The 22-year-old national athlete, Claudio Puelles, suffered an injury to his left knee during training at Team Oyama, and will undergo surgery in the coming weeks. The recovery time is yet to be confirmed.
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