DE: Jerel Worthy vs. The Field. The Packers had the worst pass rush in the league last year, an impotent and unimposing unit whose lack of disruptive pressure contributed to the worst pass defense in NFL history. They drafted Jerel Worthy (Michigan State) in the second round to fix that. But, just for good measure, they signed three free agents (Anthony Hargrove, Phillip Merling and Daniel Muir) and kept pedestrian holdovers Jarius Wynn and C.J. Wilson on the roster. Competition brings out the best, they say, and the Packers hope the glut of bodies brought in to rival Worthy does just that.

RB: James Starks vs. Alex Green. James Starks has never stayed healthy long enough for the Packers to figure out whether he’s a legitimate NFL running back. He’s big (6-foot-2, 220 pounds), fast and strong, but the consistency has never been there. Green, a third-round pick in 2011, was just beginning to show a glimmer of promise when he tore his ACL last October. He, too, has size (6-0, 225) and is a good receiver. The running backs in Green Bay are told explicitly their job is, in order of importance, to protect quarterback Aaron Rodgers, to protect the football and gain four yards a carry. If Green is healthy and a willing pass blocker, he could supplant Starks as the starter.

CB: Tramon Williams vs. Sam Shields. One of these two must return to his 2010 form, when Williams was a Pro Bowler and Shields a pleasant rookie surprise, if the Packers hope to improve the all-time worst pass defense. Craggy but crafty veteran Charles Woodson, who had seven interceptions last year, is entrenched as one starter. The Packers play a ton of nickel, so Williams and Shields aren’t so much competing against each other for a starting spot but against the potential ignominy of being burned as often and as badly as both were last year. When healthy – and he wasn’t last year, with a nagging shoulder injury – Williams is a terrific press corner who can neutralize an opponent’s top wideout. If Shields takes the next developmental step, though, and learns to tackle, he could challenge Williams for that No. 1 role.