The St. Louis Rams' upset victory at Arizona was tempered by the news that starting outside linebacker Alec Ogletree could be lost for the season.

Rams coach Jeff Fisher said Ogletree will require surgery on his right ankle after he was injured in the second half of Sunday's game and had to be carted off the field.

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Ogletree, who recorded a team-high nine tackles in the game, was hurt when teammate T.J. McDonald landed on the back of his right leg during a running play, pinning his ankle awkwardly underneath him.

The third-year linebacker had registered more than 100 tackles in each of his first two seasons and was well on his way to another with 41 tackles through the first four games. He also had a pair of sacks in last week's loss versus the Pittsburgh Steelers.

Ogletree will go on injured reserve but Fisher said it's too early to tell if Ogletree will be placed on injured reserve/designated to return. Daren Bates replaced Ogletree after he was hurt.

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