The Vikings defensive backfield keeps taking hits.
Starting cornerback Josh Robinson left Sunday's 41-20 loss at Seattle because of a fractured sternum and will miss at least a month.
All four starters in the secondary have missed games this season. Safety Harrison Smith (turf toe) is on injured reserve/designated for return and is expected back for the final three games of the season. Robinson, with six games remaining, could go on injured reserve and be lost for the season; coach Leslie Frazier said that option would be discussed.
Frazier said the injury occurred on a first-half tackle, and Robinson continued to play but was having problems catching his breath.
"We decided not to let him continue until we got a look at it, and found out today he suffered a fracture," Frazier said.
Xavier Rhodes likely will replace Robinson as the starting left cornerback, and Marcus Sherels would replace Rhodes at nickel back.
Robinson, a second-year player from Central Florida, had 58 tackles and one forced fumble this season.
Sunday surprise
Frazier was surprised wide receiver Greg Jennings didn't suit up against the Seahawks. Frazier listed Jennings as probable Friday while dealing with an Achilles' tendon injury, but Jennings was inactive Sunday.