The Green Bay Packers generally have tempered their excitement about rookies in the four years General Manager Ted Thompson and coach Mike McCarthy have been running the football side of the organization.

Receiver Greg Jennings stood out too much to be ignored as a second-round pick in 2006. But aside from him, the only other draft picks who started regularly as rookies in that time, let alone became key players, were offensive linemen Daryn Colledge and Jason Spitz.

But ask McCarthy what he thinks of Thompsons selection of outside linebacker Clay Matthews at No. 26 overall in this years draft, and theres not much tempering.

What do I think of the pick of Clay Matthews? McCarthy said. Cant you just say thats a heck of a pick in Clay Matthews?

Yes, as the 2009 season goes on, its looking more like Thompson hit it big when he selected Matthews, the former USC standout who is the son, nephew and grandson of former NFL players and a likely candidate for defensive rookie of the year.

Matthews, a starter since Week 4, has been one of the Packers better defensive players for a good chunk of the season. This week, he was named NFC defensive player of the week not defensive rookie, but defensive player. Against Baltimore on Monday night, he had six tackles, two sacks and a forced fumble in the Packers 27-14 win.

It's more than one game, though. Matthews is one of several reasons the Packers are a much improved defense from 2008.

Much of the credit for their No. 8 ranking in fewest points allowed after 12 games goes to defensive coordinator Dom Capers, who weathered some ups and downs in the first half of the season with his new 3-4 and has put together two strong games without outside linebacker Aaron Kampman and cornerback Al Harris, who were lost to season-ending injuries.

But to make an appreciable jump such as the Packers have last season they were No. 22 in the league in points allowed a team also needs ascending play from a couple of new faces, or up-and-comers already on the roster. Matthews has been one of those players as the right outside linebacker.

The speed he brings to the field, especially the pass rush, he plays like a veteran, defensive end Cullen Jenkins said. Thats huge.

When Thompson traded two third-round picks to move up from early in the second round (No. 41 overall) and draft Matthews late in the first round (No. 26), he surprised even members of his organization. Not that he liked Matthews, who was a late riser in the spring after being only a one-year starter at USC, but for trading two valuable picks to move up for only the second time in his five drafts for the Packers.

I thought at the time it was an unusual move for Ted, quarterback Aaron Rodgers said, but I realized they must have seen something special in him. The thing that struck me first about Clay, he had the right demeanor for a rookie. He came in, kept his mouth shut. He just wanted to play and play hard and wait for his opportunity. Now, it didnt come right away, he wasnt starting Day 1, and he continued to work hard and has shown himself to be a very solid player, a good professional. He competes week in and week out, and hes really helped out our team a bunch.

The Packers projected Matthews to be a starter at some point as a rookie, though a recurring hamstring injury and veteran Brady Poppinga held him back from that role until Week 4.

Either way, Thompsons investment was huge, because he chose Matthews specifically for a critical role in Capers 3-4 defense. The outside linebackers in Capers scheme are the most important playmakers. For the defense to thrive, they have to be excellent outside rushers while holding up in pass coverage and against the run.

Though Matthews isnt a lights-out speed rusher, hes shown a good combination of quickness and instincts in attaining seven sacks, which ties him with Washingtons Brian Orakpo for tops among rookies this season and for No. 13 in the league.

Matthews also has shown a complete set of skills. NFL scouts who have watched the Packers say that what stands out is the most basic of observations: He always seems to be around the ball, which is what Thompson said jumped out at him when he watched tape of USC last season.

You cant argue with the athletic ability, the versatility he gives you at that position, McCarthy said. Thats what youre looking for. The ability to put his hand down and rush the passer. Also to play all the different combinations, the pressure packages and the cover packages. I think hes off to an excellent start. When you have a rookie win the defensive player of the week, I think that speaks for itself.

Though Matthews has been a late bloomer, in one way he probably was as well prepared to play immediately as anyone in this years draft. He grew up watching what his father, Clay Matthews Jr., and to a lesser degree his uncle, Bruce Matthews, did on and off the field to forge their 19-year NFL careers.

McCarthy, Jenkins and Rodgers all brought up Matthews professionalism without being asked. Matthews appears to have learned it as much by osmosis as anything. He said football is in our DNA and that he and his father never talked much about what its like to be a rookie, which seems to have fostered a professional mindset.

I dont buy into that if youre a rookie youre not expected to produce as much or youre expected to make mistakes, Matthews said.

So (my father) talks to me, and so does everybody else, as if Im a veteran. Im doing the same thing everybody else is, and theres no excuse for not understanding a game plan or not being able to make a certain play. They brought me in for a reason, and that was to contribute right off the bat.