(John McDonnell/THE WASHINGTON POST)

Kerrigan sat out Thursday's practice and returned to the field on Friday, but sat again today.

Shanahan said he wasn't entirely sure of all of Kerrigan's symptoms; “he just wasn't feeling very well.” Shanahan said the trainers are monitoring Kerrigan and suggested that the linebacker not practice.

Kerrigan later said that he experienced some dizziness earlier this week and then again Friday.

— Shanahan said Tony Moll, signed yesterday but announced today, is going to compete as a guard. Moll has started 22 games since 2006, with the majority coming at guard, and some at tackle.

— Shanahan said that two scuffles in practice — between London Fletcher and Will Montgomery, and Markus White and Niles Paul — are part of camp, but that he told the players they need to keep their poise.

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