SAN DIEGO -- After a hearing a wave of criticism from the Internet and on talk radio about his performance through the first nine games of the season, San Diego Chargers inside linebacker Donald Butler was succinct in addressing his poor play.

"It is what it is," Butler said. "I've just got to play better."

Butler, 26, has become the embodiment of everything that is wrong with San Diego's defense of late. The Chargers are last in the league in third down and red zone efficiency. That haven't notched a sack in two games, or forced a turnover in three weeks.

Butler signed a seven-year, $51.8 million contract this offseason that includes $11.15 million in guaranteed money.

Butler had issues with staying on the field the past two seasons, missing four games each in 2012 and 2013 due to a lingering groin injury. However, the University of Washington product says he's healthy. He's played in 97 percent of his team's defensive snaps this season, is second in tackles with 57 and has a sack. Those numbers are on par with what Butler has done through his first three seasons.

But along with the missed tackles, what has been absent from Butler's performance the first half of the season is splash plays -- interceptions, sacks and forced fumbles -- the type of plays that swing the momentum of a game in his team's favor.

Butler acknowledged he's not played up to his potential so far this season.

"No, not at all," he said.

Chargers head coach Mike McCoy again reiterated Butler isn't the only person to blame for San Diego's issues on defense.

"Donald has made his fair share of plays from week to week and there are other things you got to correct," McCoy said. "We are not putting this on one player. We are all in this together, players, coaches included, we got to do a better job."

During the bye week, Butler said he's working on simplifying his approach on Sunday.

"Seeing the ball, and going to get ball," he said, with a smile.