Fusco was held out of practice Wednesday. Vikings coach Mike Zimmer has not commented on Fusco's condition. Fusco was not on the injury report last week.
The Vikings have already lost right tackle Phil Loadholt (torn Achilles tendon) for the season and center John Sullivan (back surgery) for the first half of the season. Fusco moved from the right side to the left side this year, with Mike Harris taking over as the starter at right guard.
The Vikings host San Diego on Sunday.
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