SEATTLE (AP) San Francisco running back Frank Gore suffered a concussion throwing a block in the second quarter of the 49ers' 17-7 loss to Seattle on Sunday.
His backup, Carlos Hyde, also was injured in the third quarter when his right leg was pinned underneath him as he was tackled. There was no specific announcement on Hyde's injury, but he did not return to the game.
Gore was hurt on a 22-yard pass from Colin Kaepernick to Bruce Miller. Gore was downfield on the play and crumpled to the turf after blocking Seattle's Bobby Wagner. The San Francisco sideline jumped to help Gore, who was on his back for a few moments before standing up and walking off on his own.
The 49ers announced after halftime that Gore would not return. Gore had a productive first half rushing 11 times for 29 yards and a 10-yard touchdown that gave the 49ers a 7-3 lead.
The injuries to Gore and Hyde left San Francisco with Alfonso Smith as its primary ball carrier in the fourth quarter. Smith finished with six yards on four carries.
The 49ers also lost middle linebacker Chris Borland to an ankle injury on the final play of the first half that also knocked out Seattle left tackle Russell Okung from the game. Eric Reid intercepted Russell Wilson's pass and the two players were injured on the return. Borland was hurt toward the end of the play, while Okung suffered a chest injury being blocked.
Borland attempted to play early in the second half but was too limited to continue. Okung sustained a chest-wall bruise and was taken to a hospital for further evaluation and released.
Seattle's only other injury was tight end Tony Moeaki with a shoulder injury.
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