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Tarvaris Jackson had little time to bask in celebration after his 55-yard touchdown pass to Doug Baldwin brought the Seattle Seahawks within two. He started getting ready for a potential go-ahead drive and rallying the defense on the sidelines for one, final stop.

"We were just telling the defense, 'Hey, we get this ball back, we're going to win this game,'" Jackson said. "I really felt like we were going to get the ball back and get the game."

Ted Ginn Jr. never gave them the chance.

Ginn returned a kickoff and a punt for touchdowns in a minute's span late in the fourth quarter, sending the Seahawks to a 33-17 loss to the San Francisco 49ers in the regular-season opener Sunday.

Ginn ran a kickoff back 102 yards moments after the defending NFC West champion Seahawks had closed within 19-17. It was the second-longest kick return at home and fourth-longest in team history. He then scored on a 55-yard punt return.

It was the first time in 49ers history they had a kickoff return and a punt return for touchdowns — let alone by the same player — to highlight a surprising turnaround that left the Seahawks stunned.

"It was just strange the series of events that went on," Baldwin said. "I felt like I was so caught up in the moment of scoring a touchdown. I didn't feel like I was prepared. It was just shocking for them to go down and score another touchdown."

The Seahawks fell behind 16-0 at the half and spent the entire game playing catch-up.

Alex Smith exhibited the poise and polish Harbaugh believed the 2005 No. 1 overall pick still had in him despite recent history, going 15 for 20 for 124 yards and running for a 1-yard TD. David Akers kicked four field goals in his first game with San Francisco.

Jackson threw a late 55-yard touchdown pass to Harbaugh's former Stanford star, Baldwin, in his Seahawks debut as Matt Hasselbeck's replacement. He was under constant pressure but managed to keep Seattle close.

After serving as Brett Favre's backup in Minnesota the past two seasons, Jackson completed his first six passes but was sacked twice in as many drives to start the game — by Ray McDonald and Justin Smith — and five times total. He finished 21 of 37 for 197 yards and two TDs with one interception.

Harbaugh pulled Smith into a seconds-long bearhug after he hustled to the sidelines after his short TD run just before halftime in which he spun into the end zone to put the 49ers up 16-0. Ginn saved the game with a huge day on special teams. He also returned kickoffs of 100 and 101 yards for touchdowns in a 30-25 win for Miami over the New York Jets on Nov. 1, 2009.

Seahawks coach Pete Carroll wasn't even sure Ginn would return kicks after a quiet preseason.

"I didn't amaze myself but I didn't think they were going to come right back and kick it to me," Ginn said. "I wanted to make them pay."

Dozens of American flags whipped in the wind off San Francisco Bay in the parking lots of sold-out Candlestick Park before the game on the 10th anniversary of Sept. 11. Flags inside flew at half-staff and many of the 69,732 fans sported red, white and blue.

Rivals dating to their days in the Pac-10, Seahawks coach Pete Carroll couldn't complain about Harbaugh running up the score in this one. Seattle's offense had enough problems for Carroll to worry about what was happening on the other sideline.

The two quickly shook hands afterward and called it good.

Akers kicked field goals of 27, 24, 31 and 18 yards in an impressive first game with the 49ers in place of the retired Joe Nedney. First downs were scarce for Seattle with San Francisco's defense stingy behind defensive tackles McDonald and Smith.

The Seahawks, 7-9 last year before stunning the reigning Super Bowl champion Saints in the playoffs for the first victory by a team with a losing record, have their work cut out for them to defend in a division that became known as the NFC Worst in 2010.

One telling moment Sunday: Jackson was sacked by Parys Haralson, who forced a fumble that was recovered in the air by Will Tukuafu on his first career play from scrimmage. That set up Akers' second field goal.

What a difference from last year's opener between the division foes.

The 49ers lost at Seattle 31-6 last September on the way to a surprising 0-5 start that dashed San Francisco's hopes of winning the division. All it took was two returns to change this season.

"It was just so uncharacteristic of the way we play," Carroll said. "We count on those guys to do a fantastic job that they did all of last year. And in two swings, they took this game away from us."

Notes: Pro Bowl TE Zach Miller had two catches for 19 yards in his Seattle debut. He led the Oakland Raiders in receiving the past two seasons... WR Ben Obomanu said he was fine after taking a hit to the helmet from S Donte Whitner ... Seahawks FB Michael Robinson injured his ankle in the first quarter and didn't return.