EAST RUTHERFORD, N.J. -- The New York Giants 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 2½ sacks were his most in a game 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.

"I feel all right," said Dilfer, who threw for two touchdowns, including a meaningless one late to Darrell Jackson. "I'll probably be pretty sore tomorrow. I'm disappointed, but the body is hanging in there."

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.

"When your defense plays that well, they really make it easy on you offensively," Giants center Shaun O'Hara said. "I felt like we were getting the ball on their side of the 50-yard line all day long. That makes for a long day for them."

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

"They bring enough pressures right when you think you're getting comfortable," Dilfer said. "They do a good job making adjustments and overloading you. By the end of the deal, they are going to be one of the better defensive teams in the league."

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 New York's 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.

Dilfer, who couldn't get together with Gore on the handoff that led to the fumble, made another mistake on the next play from scrimmage when he didn't see Sam Madison on a short pass. The Giants cornerback jumped the route and intercepted the pass, setting up Tynes' 29-yard field goal for a 16-7 edge.

Tynes, who missed the extra point on the Giants' opening drive that Manning capped with a 4-yard pass to Toomer, added a 39-yard field goal just before the half.

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 in 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.

"Every time 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 had 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.

Copyright 2007 by The Associated Press. All Rights Reserved