Watford _ The Vikings' first full-fledged press conference in London offered some startling news: Quarterback Christian Ponder injured his ribs against the Browns on Sunday and is not certain to play against the Steelers.

Ponder spoke at the team hotel before Vikings' practice. He said he was able to throw the ball during the team's walk-through, but coach Leslie Frazier said he needed to evaluate Ponder during practice and would make a decision by Friday afternoon.

Matt Cassel would start if Ponder was unable to play.

Ponder said he injured his ribs on a play early in the Browns game. He was able to finish the game.

-Vikings GM Rick Spielman wouldn't comment on whether he has reached out to former Vikings cornerback Antoine Winfield. Safety Jamarca Sanford and cornerbacks Chris Cook and A.J. Jefferson will not practice today because of injuries.

Spielman said his staff in MInnesota is looking for roster depth but wouldn't comment specifically on Winfield. Spielman usually doesn't speak publicly during the season but made an exception to meet with the London and U.S. press covering his team's practice at the team hotel on Wednesday. Owner Mark Wilf, Frazier, Ponder and Adrian Peterson also spoke.

-Not much news came out of the Peterson press conference, but one Brit did ask whether he would consider expanding his acting career, perhaps to become the next James Bond.

``I'll have to take acting lessons," Peterson said with a smile.

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