San Francisco 49ers’ Vernon Davis (85) makes a catch against the Green Bay Packers in the third quarter at Candlestick Park in San Francisco, Calif.
San Francisco 49ers' Vernon Davis (85) makes a catch against the Green Bay Packers in the third quarter at Candlestick Park in San Francisco, Calif. on Sunday, Sept. 8, 2013. (Nhat V. Meyer/Bay Area News Group) ( Nhat V. Meyer )

SANTA CLARA -- When the 49ers visit Seattle on Sunday night, they'll be getting a chance to show that last December's 29-point blowout was an anomaly.

"We're going up there to prove that's not who we are," quarterback Colin Kaepernick said Wednesday of that 42-13 defeat.

The 49ers and Seahawks are both 1-0, and the similarities don't stop there in this hot NFC West rivalry. Defensive dominance, state-of-the-art quarterbacks, animated coaches and Super Bowl expectations are common themes.

This will be the first chance for these teams to distance themselves from each other, and the Seahawks are out to repeat last year's home-field heroics.

"It happens to be the home opener for us, which is an enormous opportunity to get this home season cooking," Seahawks coach Pete Carroll said on a media conference call.

The Seahawks' 8-0 home record last season was highlighted by the December win over San Francisco, Carroll's first victory in four games against the Jim Harbaugh-coached 49ers.

Sunday's rematch could be much different from their last meeting in Seattle. Yes, it will be on the prime-time stage again. But this time rain isn't in the forecast, Justin Smith isn't sidelined with a triceps tear, and the 49ers aren't coming off a tough, cross-country win a week earlier in New England.

Running back Frank Gore called that loss at Seattle "tough. They beat us good." Kaepernick summed it up as simply a bad game.

It indeed was bad for Kaepernick. He posted a career-worst passer rating of 72.0 on 19-of-36 passing for 244 yards with one touchdown and one interception. Now he's coming off a career-high 412 passing yards in a 34-28 season-opening win over the Green Bay Packers.

The 49ers converted just 3 of 11 third-down chances in their last meeting with the Seahawks, and that was an area of emphasis this offseason. They responded by converting 9 of 18 third downs against the Packers, including Kaepernick's first two touchdown passes.

"There was definitely some improvement, and we're working hard to continue that," Harbaugh said.

One area the 49ers haven't cleaned up is their communication before plays. Play-clock issues hindered them in Sunday's opener.

Seattle's crowd noise won't make things easier. Its fans are hoping to set a Guinness World Record as the loudest crowd ever, a movement originated by former Seahawks defensive lineman Joe Tafoya, a Pittsburg native.

Defensively, the 49ers won't be surprised this time by Seattle quarterback Russell Wilson's ability to elude pass rushers -- all of whom are at full strength, including Aldon Smith, who had a torn labrum and had no sacks in Seattle.

Personnel-wise, the 49ers and Seahawks cat-and-mouse moves this offseason included same-day trades for wide receivers Anquan Boldin and Percy Harvin. While Boldin had 208 receiving yards and a touchdown Sunday, Harvin is out through at least November after hip surgery.

Among other personnel moves, Phil Dawson has taken over as the 49ers kicker for David Akers, who had a field-goal attempt blocked and returned 90 yards for a touchdown last year by Richard Sherman in Seattle. Also, the Seahawks acquired defensive end Cliff Avril, who has battled a hamstring injury but is expected to make his season debut Sunday.

Sunday's game falls on Carroll's 62nd birthday. It happened to be Harbaugh's 49th birthday when the teams' last met, prompting Sherman to say afterward on the NFL Network: "Happy birthday Coach Harbaugh. Hope you enjoyed it."

San Francisco 49ers’ Vernon Davis, left, is hit by Seattle Seahawks’ Kam Chancellor, right, during a reception attempt in the first half of an
San Francisco 49ers' Vernon Davis, left, is hit by Seattle Seahawks' Kam Chancellor, right, during a reception attempt in the first half of an NFL football game, Sunday, Dec. 23, 2012, in Seattle. (AP Photo/John Froschauer) ( John Froschauer )

  • Special-teams ace Kassim Osgood returned on a one-year contract Wednesday, filling the roster spot of rookie Nick Moody, who was placed on injured reserve with a designation to return from a broken right hand. Teams are allowed to use the short-term I.R. designation only once during the season.

  • Running back LaMichael James (knee) did not practice while all others did without limitations.

  • In an effort to weed out unruly fans, the Seahawks say they will have undercover police officers wearing opposing team apparel beginning with the game against the 49ers.

    The Associated Press contributed to this report.

    SUNDAY'S GAME

    49ers (1-0) at Seattle (1-0), 5:30 p.m. NBC