The Jacksonville Jaguars traded receiver Dennis Northcutt to the Detroit Lions for safety Gerald Alexander. Northcutt gives rookie quarterback Matthew Stafford, the top pick in April’s NFL draft who could replace Daunte Culpepper in the starting lineup, a veteran receiver opposite Calvin Johnson. Alexander, a second-round pick in 2007, gives Jacksonville depth in the secondary. He started 16 games as a rookie, but missed most of last year following a neck injury.