SEATTLE Larry Grant did his best Justin Smith impersonation late in the fourth quarter.
With the Seahawks driving for a last-minute go-ahead field goal, the 49ers inside linebacker ran down Seattle's Tarvaris Jackson, saw the ball hanging loosely from the quarterback's hand and took a big whack with his right hand. Grant's chop knocked the ball free, and safety Donte Whitner recovered at the 49ers' 36 with 1:07 left to preserve San Francisco's 19-17 win Saturday.
Jackson initially eluded Grant, but the linebacker kept pursuing.
"He didn't tuck it at all," the Foothill High School product said. "He keeps it loose and keeps his eyes downfield. Knowing he does that, it was just, hit him from behind."
Said coach Jim Harbaugh: "It was again a great hustle play. We've had a bunch of those."
Defensive end Smith twice has been the 49ers' end-of-game hero. He forced a fumble to preserve a win against Philadelphia in Week 4, then batted down Eli Manning's last-second touchdown-pass attempt in a Week 10 victory over the New York Giants.
The Seahawks did end two impressive streaks by the 49ers' run defense.
Seattle's Marshawn Lynch ran for 107 yards, ending at 36 games the 49ers' streak of holding opposing rushers to fewer than 100 yards. He became the first rusher to break the 100-yard barrier against San Francisco since Green Bay's Ryan Grant in November 2009.
Lynch's four-yard touchdown run in the fourth quarter also was the first rushing score against the 49ers this year.
Still, nobody was talking about the spoiled streaks after Saturday's game.
For the third straight week, Grant started in place of Patrick Willis, who did a few linebacker-like drills dropping back in coverage, shuffling between cones before the game but was held out to rest his still-recovering right hamstring.
Willis said he watches Grant on each play so he can give him advice. Willis also said he saw the forced fumble developing.
"That's what we talk about all the time as a defense never giving up and just hustling to the ball," Willis said.
Milestones David Akers' 44-yard field goal early in the fourth quarter landed him in the NFL record books. It was Akers' 41st field goal of the season, one more than Neil Rackers had in 2005 for Arizona.
Akers also connected from 53 and 29 yards, and he hit the decisive 39-yarder with 2:57 to play. He also missed from 52 yards.
The 49ers' offense also is on the verge of tying a record after finishing without a turnover. Through 15 games, the unit has committed only 10 turnovers five interceptions and five fumbles.
If the 49ers avoid giving up the ball in next week's regular-season finale against St. Louis, they will become only the second team since 1946 to have as few as 10 turnovers. New England accomplished that last season.
Injuries The 49ers suffered several injuries Saturday, most notably one to Delanie Walker. The tight end inadvertently was kneed on the side of the head in the first half and taken to a hospital with what teammates suspected was a broken jaw. He flew back with the team.
Return man Kyle Williams left after being sandwiched by two defenders on a kickoff return. Justin Smith (leg) and linebacker Ahmad Brooks (elbow) briefly left in the first half but returned.
49ERS' REPORT CARD
Offense: The 49ers again relied more on field goals than touchdowns. But the unit came through with a gritty fourth-quarter scoring drive when the Seattle crowd was at its loudest. Grade: B
Defense: Linebacker NaVorro Bowman had a strong game for a defense without Patrick Willis for the third straight game. Larry Grant did his best Justin Smith impersonation with a game-sealing forced fumble. Grade: A-
Special teams: David Akers set the NFL record for field goals in a season. Kyle Williams filled in nicely for Ted Ginn as a return man. But a blocked punt late nearly cost the 49ers the game. Grade: C+