Jadeveon Clowney can be a game changer when healthy. The former No. 1 overall NFL draft pick terrorized 49ers quarterback Jimmy Garoppolo when the Seattle Seahawks beat San Francisco 27-24 on Nov. 11 at Levi's Stadium.

Clowney registered five solo tackles, five QB hits, one sack and returned a fumble he forced and recovered for a touchdown. That's a dominant performance.

But Clowney has missed Seattle's last two games with a core-muscle injury. The defensive end, however, told reporters on Thursday that there's "no doubt" he is playing Sunday against the 49ers.

Jadeveon Clowney said there’s no doubt he’s playing this Sunday against the 49ers. Huge for the Seahawks. — Joe Fann (@Joe_Fann) December 26, 2019

Clowney, 26, has played in 12 games this season. He has recorded 30 tackles, three sacks, 13 QB hits, four forced fumbles, two fumble recoveries and one interception.

Despite missing time to injuries this season, there's no way Clowney will sit out Sunday as these two teams clash for the NFC West title. The six-year veteran says it feels like the Seahawks are "preparing for war."

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That's a bit extreme, but Sunday undoubtedly is the biggest game in the NFL all season long.

Despite the return of running back Marshawn Lynch, the 49ers likely are more worried about Clowney's return.