The 49ers coaching staff wanted to make Fridays practice so taxing on the defense that Sunday would seem like a breeze by comparison. San Francisco’s Michael Crabtree makes a one-handed pass reception for a two-yard gain against the Philadelphia Eagles at Levi’s Stadium, Sunday, September 28, 2014 in Santa Clara, Calif. Colin Kaepernick runs for a seven-yard gain in the second quarter against the Philadelphia Eagles on Sunday at Levi’s Stadium in Santa Clara, Calif. San Francisco 49ers fans cheer on their team in the fourth quarter in a game against the Philadelphia Eagles at Levi’s Stadium, Sunday, September 28, 2014 in Santa Clara, Calif. Michael Crabtree runs after losing his helmet in the second quarter against the Philadelphia Eagles on Sunday at Levi’s Stadium in Santa Clara, Calif.