Starting right tackle Phil Loadholt was placed on injured reserve Wednesday after he tore a left pectoral muscle Sunday in the loss to Green Bay.
Mike Harris will replace Loadholt in the lineup, and Webb will back up Harris and left tackle Matt Kalil. Undrafted rookie Austin Wentworth is the other tackle on the active roster. He has appeared in only two games this year.
Webb played for the Vikings in 2013, appearing in eight games and starting one. He was in training camp with Kansas City but let go before the season. Webb played the first three years of his career with Chicago.
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