SEATTLE -- For three straight seasons, Jim Harbaugh's 49ers have finished oh-so close.
The NFC championship game after the 2011 season and again this year, and last season's 34-31 Super Bowl defeat to the Baltimore Ravens. And they have lost them all in a most frustrating fashion: Each time, with a great chance to win.
Quest for Six will have to wait at least one more year after the Niners lost a chance for a return trip to the Super Bowl in a 23-17 loss to archrival Seattle on Sunday.
"It's great competition," Harbaugh said. "Not many people get to be in this arena. I'm proud of our guys for the fight they showed today and all season."
In a scene reminiscent of the way last season ended in the New Orleans Superdome in the Super Bowl, Colin Kaepernick threw a pass in the end zone intended for Michael Crabtree. This time, Richard Sherman deflected the ball right to Malcolm Smith for a game-sealing interception.
Harbaugh knows special seasons can be fleeting. All he has to do is turn to big brother, John, whose Ravens failed to even reach the playoffs 11 months after winning a championship.
Colin Kaepernick and the San Francisco 49ers knew one or two turnovers could cost them a return trip to the Super Bowl.
That had been the case in their past two visits to Seattle, so taking care of the ball became a top priority for San Francisco to beat the Seahawks on their home field.
Kaepernick went 14 for 24 for 153 yards with two sacks and two interceptions, and the 49ers committed three fourth-quarter turnovers that made the difference through the deafening noise of CenturyLink Field.
"You can't point fingers," right tackle Anthony Davis said. "We came out here as a team, we win as a team, and we just lost as a team."
It hurt even more to see two key players from either side of the ball go down with serious injuries -- All-Pro linebacker NaVorro Bowman with a likely torn left knee ligament, and left guard Mike Iupati with a left ankle that is believed to be broken.
"We had a shot," punter Andy Lee said. "That's what we wanted. It was a good year with these guys. Hopefully we can get back to work and come back all fine next year."