Chargers’ linebacker Stephen Cooper has been suspended for four games for violating the NFL’s substance abuse policy.  This is a huge loss for the Chargers as Cooper really broke out last season for them.  Cooper played in all 16 games for the Chargers last season and he made 108 tackles, defended 6 passes, had 2 sacks, forced 2 fumbles and intercepted 2 passes.  Cooper has now played in 80 games in his NFL career and he has made 259 tackles, defensed 11 passes, has 7 sacks, forced 3 fumbles and intercepted 3 passes.  The Chargers signed linebacker Derek Smith in the off-season and he will likely replace Cooper as the starter at inside linebacker the first four games of the 2008 season.