Or rather, the lack of production.
No tackles in two straight games, according to STATS and the NFL. No sacks. One quarterback hurry.
The Packers were slightly more generous with their own stats, listing him with a half-tackle in that period.
''Yeah, I mean someone was joking about that with me the other day. It's obviously a stat that you don't like hearing,'' Matthews said. ''But at the same time, I'll just continue to do what I need to do ... and at the same time be a little more, hopefully, impactful and be around the ball.''
Tackles alone aren't an accurate gauge of a player's effectiveness, especially for a star like Matthews. He's got pedigree as a pass rusher, with 66 1/2 sacks in his seven-year career, so it's a priority for offenses to locate him on the field before the snap.
Watch any defensive highlight reel of the Packers, and it's bound to include a clip of Matthews taking down a quarterback while his long blond hair flies out of his helmet.
''Well, Clay Matthews is clearly our most disruptive player. Statistics I don't think ever always tell the full story,'' coach Mike McCarthy said. ''You look inside the statistic or the performance, so I don't think it's an indication of anything.''
Still, this is a streak that he would like to end. There would be no better time than on Sunday night against the Minnesota Vikings with NFL leading rusher Adrian Peterson in town and the NFC North title on the line.
Defensive coordinator Dom Capers is fond of saying that a few plays each week alter the course of the game.
''I pride myself on being that guy who does it once or twice in a game, whether it's the (tackles for losses) from the last Minnesota game or whatever it may be, I've got to find a way to show up,'' Matthews said. ''And I will.''
In the teams' last meeting against Minnesota, a 30-13 road win, Matthews had six tackles, including two for losses. Peterson was held to 45 yards on 13 carries, and Matthews said it was a function of the defense being aggressive and limiting Peterson on the edge.
Matthews' role overall has changed over the last two season. Once primarily an outside linebacker, Matthews was moved to the middle at the midpoint of the 2014 season to help shore up the run defense. He went back to his more customary position on passing downs.
The move worked and the Packers improved against the run. This year, Matthews has been playing inside even more, and he still made his sixth Pro Bowl.
Assignments are different inside, where Matthews must call defensive signals. Stopping the run is even more of a priority, while Matthews might be matched up against athletic tight ends in passing situations.
''Some games the opportunities are there and some games they're not,'' Matthews said when asked if the lack of tackles might be a function of offenses adjusting to his role. ''It's a product of moving around and what's being asked.''
Matthews continued, ''I wouldn't put too much weight on that. But, at the same time, yeah, if you're one of 11 guys that day, you need to show up, obviously on film but ... on the stat sheet as well.''
At least an ankle injury that has bothered Matthews for nearly two months appears to be getting better. He has been a full participant in practice this week after being listed as limited in previous weeks.
NOTES: DT B.J. Raji (concussion) returned to practice Thursday on a limited basis after missing Wednesday's lighter workout. ... Top CB Sam Shields (concussion) was limited for a second straight day. McCarthy had said before practice that Shields was in the latter stages of the concussion protocol. ... RB Eddie Lacy (rib) was limited and called his injury a ''pain tolerance thing, and I think I have pretty good pain tolerance.'' ... LT David Bakhtiari (ankle) missed a second day of practice.
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