SAN FRANCISCO - 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.

Seattle 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."