The San Francisco 49ers placed their leading receiver from last season, tight end Eric Johnson, on the injured reserve Thursday with a torn muscle in his left foot. "I can't believe it," Johnson said while on crutches in the 49ers' locker room, his foot in a protective boot. "I've just got to roll with the punches and come back better than ever this year. I think I went through a lot of this stuff in 2003, mentally coming to grips with not playing."