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Minnesota Vikings cornerback A.J. Jefferson suffered a concussion late in his team's 21-14 victory over the Chicago Bears on Sunday. The injury occurred when Jefferson collided with one of his teammates, and may have been knocked unconscious. Head coach Leslie Frazier said after the game that Jefferson would undergo further evaluation during the week.
Jefferson is in his first season with the Vikings and his third in the NFL. He has made five starts this year and appeared in 12 games, missing only the season-opener against Jacksonville. He made four tackles against the Bears and has 22 for the season.
Prior to joining the Vikings, Jefferson spent two seasons with the Arizona Cardinals, where he made seven starts and appeared in 18 games, including all 16 last season. Over the course of his career, he has collected 89 tackles and one interception.
The Vikings return to the field to face the St. Louis Rams on Dec. 16.