GREEN BAY, Wis. — When they sit down together next month to evaluate what went wrong with the 2008 Green Bay Packers, general manager Ted Thompson and coach Mike McCarthy will have to be honest with themselves.

They'll have to raise the possibility that they erred in believing a young team with a young quarterback could repeat the success of a 13-3 season.

It isn't necessarily a question of Brett Favre vs. Aaron Rodgers, but rather why in Year 4 of Thompson's tenure as GM are they the youngest team in football for the third year in a row? And are all the mental mistakes the players have made this season the result of the way this team has been built?

One thing is clear after a fourth straight loss that dropped the team's record to 5-8: There are fundamental errors being made that a team should not be making less than a year after playing in the NFC Championship Game.

"When we're sitting here in Week 15 talking about miscommunication, that concerns me," coach Mike McCarthy said Monday, a day after a bitter 20-16 loss to the Jacksonville Jaguars. "It's been addressed with the team at halftime, and we'll go back in there today at 2:45 and go through every instance that happened yesterday. That's something that you need to move past.

"Now, does it happen in games? Yes it does. Is it highlighted now because we lost the game? Absolutely, and I understand that, and there's more frustration involved because we did not win. That's the reality of it."

McCarthy would not be one to subscribe to the notion that the Packers are too young to handle lining up in the right formation on a critical third-down play at the 5-yard line or to offer help on a blocking assignment that would have prevented a critical fourth-quarter sack or to avoid leaving uncovered a tight end split wide to the right or to correctly play a simple zone coverage that would have stopped a 41-yard reception on the game-deciding drive.

Those are just a handful of things that went badly Sunday at Jacksonville (Fla.) Municipal Stadium against a team that came into the game with its own problems. At a time when Green Bay teams are known for being their strongest, the Packers are playing as if they have just been introduced to their offensive and defensive schemes.

Nothing is guaranteed after a successful season, but this is a team that has nearly completed three seasons running the same schemes. And it can't line up correctly? It doesn't know how to play zone coverage? It can't block correctly?

"I look at every opportunity, every team, it's a different team no matter if you have everybody back," McCarthy said. "I've had experiences in my past where I've been on a very successful team and then you keep the same players, you move on, and you either achieve that success or you don't because of different obstacles and challenges that you have.

"I'm in the fight, and I'm in charge of winning football games. And it starts with me. The last four weeks we haven't done the things necessary to win a game, and I need to get that fixed."

It's easy to pick on the defense for its inability to hold a lead, particularly at the end of games. Some of the physical errors are understandable given the number of injuries the team has suffered and some of the replacements with whom it is forced to play.

But that doesn't excuse a veteran safety from bailing from his middle position and getting caught in no man's land or a linebacker and a cornerback arguing over who should cover which receiver. It's not as if defensive coordinator Bob Sanders is working with a bunch of guys who have never played in his system.

"Our meetings are good and guys seem to be studying and working hard," Sanders said. "So many times when something you're responsible for doesn't go as you planned, you try to evaluate yourself to see if there's anything you can do better. It's my job to get it done. At certain times it didn't.

"I just have to continue to evaluate the way we're doing things and teaching things and making sure they're getting everything in practice they need to see."

With two games left that have no bearing on the Packers' standing in the NFC North, it's a little late for any of the coaches to be considering drastic changes in the way they do things.

As they head into a long week leading up to a Monday night game against the rival Chicago Bears, it is the coaches' duty to make sure the team doesn't fold its tent for the season. About the only thing left to play for in this season is some kind of positive feeling about the potential for next season.

"The last thing I said to the guys offensively, said to the entire unit, I put up the word 'pro,' put up the definition from the dictionary," offensive coordinator Joe Philbin said of a meeting Monday. "We're all professionals, players and coaches. We all have responsibilities to each other.

"We believe in these players. I think our players believe in us as a coaching staff. We have to come back to work and see if we can put a positive finish on the season."