Vikings' Robinson has fractured sternum

Eden Prairie, MN ( - Minnesota Vikings cornerback Josh Robinson will be out at least 4-to-6 weeks because of a fractured sternum, coach Leslie Frazier announced during Monday's press conference.

Robinson suffered the injury in Sunday's 41-20 loss to the Seahawks. Frazier also announced that center John Sullivan sustained a concussion during the game.

The 22-year-old Robinson has 58 tackles and four passes defensed in 10 starts this season. Xavier Rhodes will likely take Robinson's left cornerback spot in the base defense, and Marcus Sherels would be the slot cornerback in the nickel.

Frazier did not say whether they would place Robinson on injured reserve yet with six weeks left in the season.

Sullivan will have to go through the NFL's testing protocol before he can return to action.

Frazier also said that running back Adrian Peterson, who was hampered by a groin injury Sunday, would be evaluated this week.

The Vikings play at Green Bay on Sunday.