Clark, who leads Seattle with 11 sacks, was responding to comments made last month by his former teammate, now with the San Francisco 49ers, that the Seahawks were a "middle of the road" team. Sherman made his comments before the 49ers' first meeting with the Seahawks this season, when Seattle was 6-5. The Seahawks won that game 43-16 at CenturyLink Field.
The Seahawks, now 8-5, can clinch a playoff spot by beating Sherman's 49ers at Levi's Stadium on Sunday.
"He's not in this locker room no more, so his opinion really doesn't matter," Clark told reporters. "They've got some problems over there in San Fran that he needs to be worried about.
"... This is my team now. This is my defense. Richard Sherman, his era is over here," Clark continued. "If he's got anything to say about our defense, he can say it on the field, at the end of the day.
"We're 1-0 against Richard Sherman right now. We are 1-0 against the San Francisco 49ers this year. Our plan is to be 2-0. So we are going into that stadium next week with our pure aggression. We are going to stop that run, and we are going to have fun on third downs."
Sherman, a three-time All-Pro cornerback, is in his first season with the 49ers after being cut by the Seahawks in the offseason. Many thought the Seahawks might take a step back this season after he was released, safety Kam Chancellor retired and defensive end Michael Bennett was traded to the Philadelphia Eagles, but Seattle would be the fifth seed in the NFC playoffs if the season ended today.
The 49ers are 3-10 this season.