EAST RUTHERFORD, N.J. - The New York Giants' defense not only got into Trent Dilfer's head, they got to his back, his side and every other part of his body.

Dilfer became the latest quarterback to suffer the wrath of Osi Umenyiora, Michael Strahan and Steve Spagnuolo's sack-happy defense Sunday. The Giants won their fifth straight with a 33-15 victory over San Francisco, handing the 49ers their fourth straight loss.

“I think when you've done what we've done the last four or five games and start having pressure like that, before the game the quarterback is thinking about the rush,” said Strahan, whose 2.5 sacks were his most since 2003.

Dilfer certainly felt the pressure all game.

The Giants (5-2) sacked him six times, with the biggest being a third-quarter takedown by Umenyiora that resulted in the perfect play - a sack, forced fumble, fumble recovery and 75-yard return for a touchdown that iced the game.

“I don't think I have seen a guy get all four on one play,” said middle linebacker Antonio Pierce, whose interception set up a touchdown on a day the defense helped to account for 24 points against the league's worst offense.

New York forced four turnovers by the 49ers (2-4) and made Dilfer play with his head on a swivel while Alex Smith rested his ailing shoulder on the sidelines.

Eli Manning threw touchdown passes to Amani Toomer and Jeremy Shockey, and Brandon Jacobs ran for a career-high 107 yards and a touchdown for the Giants, who also got two field goals from the struggling Lawrence Tynes.

After giving up 80 points in its first two games, the Giants' defense has surrendered 53 in its last five, not counting 16 points on special teams and offensive mistakes. The have recorded 25 sacks in the winning streak.

Dilfer had thrown a 17-yard touchdown pass to Arnaz Battle to give the 49ers a 7-6 lead early in the second quarter before the Giants' defense took over.

Umenyiora set up the Giants' go-ahead touchdown in the second quarter, recovering Frank Gore's fumble at the 49ers 27.

Four plays later, Jacobs powered around the right side and scored from 5 yards for a 13-7 lead.

Manning, who was a so-so 18-of-31 for 146 yards in a game the Giants dominated, completed passes of 24 yards to Toomer and 18 to Plaxico Burress on the two-minute drill.

Umenyiora broke it open on the opening possession of the third quarter.

With the 49ers at the Giants 15 with a first down, the defensive end came around the right side, sacked Dilfer and knocked the ball out of his hands. He quickly got up, grabbed the ball and ran down the field with nothing but Giants surrounding him. At about the 5-yard line, he tiptoed into the end zone, backing in to put an exclamation point on his touchdown that put New York ahead 26-7.

“Everytime I stripped the ball, I never recovered,” Umenyiora said. “This time, the ball just bounced into my hands and I took it to the house.”

Pierce, called for two foolish roughing the passer penalties against Dilfer, atoned in the fourth quarter, picking off a pass deep in 49ers territory and returning it to the 5.

Manning found Shockey for a score a couple of plays later.

Dilfer finished 23-of-38 for 209 yards in his second start since Smith was hurt late in September. Gore finished with 88 yards on 14 carries, but the 49ers' offense didn't improve much coming off a bye week.

Notes: Burress has his six-game touchdown streak ended. ... Tynes has missed two extra points this season. ... Moran Norris blocked Jeff Feagles' punt for a safety. ... Toomer's TD catch was his 49th, giving him the Giants' career record with one more than Kyle Rote.