GREEN BAY, Wis. -- They're taking water breaks and serving snacks during training camp practices. They're using a GPS system to monitor players' movements.

They changed their practice plan, flip-flopping their Friday-Saturday in-season schedule, and even within those individual practices they moved drills that used to be at the beginning to the end, and vice versa.

All for one reason: To reduce the injuries that have befallen the Green Bay Packers in recent years.

And what good has it done?

They already have lost two players -- rookie receiver Jared Abbrederis and offensive lineman Don Barclay -- who almost certainly would have been on the opening day roster. Both suffered torn anterior cruciate ligaments within the first two weeks of practice.

Some injuries -- no matter what the training staff does to keep players energized for practice and regardless of how coach Mike McCarthy designs his schedule -- just have to be chalked up to bad luck.

"Watch either one of those things as it happened, it wouldn't give any sort of indication that it was going to be a bad deal," Packers general manger Ted Thompson said. "It's just the way it turned out."

But so far in camp, the number of missed practices due to muscle or fatigue-related injuries has been low. A year after hamstring pulls were the order of camp, the only serious muscle pull in the first two weeks was an oblique strain suffered by starting strong safety Morgan Burnett.

THREE REASONS FOR OPTIMISM

A rejuvenated Aaron Rodgers is showing no aftereffects -- so far -- of last season's broken collarbone. Benny Sieu/USA TODAY Sports

1. Quarterback Aaron Rodgers turned 30 in December and is coming off the worst injury of his career (a broken collarbone), but you would never know it by watching him now. He has been humming along in training camp as well as he ever has. His command of the offense is so great that McCarthy has been able to cut several practices short because they have not been forced to repeat plays ruined by mental errors. Rodgers reported to camp about 11 pounds lighter than he was last season, thanks to a combination of workouts (which included yoga) and diet.

2. If there's such a thing as a distraction-free training camp, this has been it. They addressed their No. 1 contract concern by signing receiver Jordy Nelson to a four-year, $39 million extension on the morning camp opened. A few days later, they locked up Thompson with a multiyear extension and said McCarthy would be next. And perhaps they have finally put any bad vibes from Brett Favre behind them when they announced last week that their former quarterback will have his number retired next summer, when he also will be inducted into the Packers Hall of Fame. All of that has allowed the team to focus on its preparation without anything getting in the way.

3. The biggest area of concern last year, the safety position, now may be one their strengths. Micah Hyde's switch from cornerback has gone better than expected, and first-round draft pick Ha Ha Clinton-Dix looks game-ready. Then there's third-year safety Sean Richardson, who has made perhaps more big plays in practice than anyone on defense. If Burnett comes back soon from his oblique strain -- and finally starts to perform like the Pro Bowl-caliber player they thought he was when they gave him a four-year, $24.75 million extension last summer -- then there should not be any concerns.

THREE REASONS FOR PESSIMISM

1. The Packers still do not know -- and may not know for a while -- whether JC Tretter can handle the starting center job. After a rough start to training camp, the second-year pro seemed to settle into the position and was solid in the preseason opener. But given the opener is at the defending Super Bowl champion Seattle Seahawks in perhaps the loudest stadium in the league, there's probably nothing that can prepare Tretter for what he will have to deal with in Week 1.

2. As good as the Packers feel about Nelson, receiver Randall Cobb and running back Eddie Lacy, they don't have many other proven weapons for Rodgers. No one from the tight end group has emerged as the favorite to replace Jermichael Finley, although Andrew Quarless, Brandon Bostick and rookie Richard Rodgers have had their moments (both good and bad). And among the receivers, Jarrett Boykin has been no better than average in his quest to replace James Jones as the No. 3 receiver. Every time it looks like rookie Davante Adams may take that job from Boykin, he drops a ball.

3. Outside linebacker Clay Matthews participated in every practice during the first two weeks but still is not ready to proclaim his twice-broken right thumb 100 percent. Perhaps it's more of a mental hurdle for Matthews, but he needs to be able to use his hand without restrictions in order to return to his Pro Bowl level. It's hard to tell if Matthews is babying the injury, but in the first two weeks of practice, he took only two reps in the one-on-one pass-rushing drill and lost both. He played a few snaps early in the preseason opener against the Titans and did not seem to have any issues.

B.J. Raji, back at nose tackle after spending last season at defensive end, has had an impressive camp. AP Photo/Morry Gash

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