Hasselbeck’s scoring throws to Jackson, Nate Burleson, Bobby Engram and even third-string tight end Will Heller — plus Shaun Alexander’s 2-yard score — put the Giants behind 35-0 for the first time since Sept. 4, 1995, when they lost by that score to Dallas en route to a 5-11 season.

“You don’t expect to be in that situation,” Seahawks coach Mike Holmgren said.

The rout was so quick, so decisive, it rendered the incessant roaring of a Qwest Field-record crowd of 68,161 moot — but not mute. The fans were mostly mocking the stunned visitors by the end of the third quarter, after the Seahawks completed a 17-play drive that ended with Darrell Jackson’s second touchdown catch for a 42-3 lead.

Manning’s initial mistake was not seeing Ken Hamlin lurking behind Plaxico Burress on New York’s third play, after the Giants’ Corey Webster had outfought Jackson for an interception to begin the game. Hamlin jumped in front of Burress, intercepted Manning’s pass and returned it 37 yards to the New York 15.

Two plays later, Alexander scored on a 2-yard run. Alexander played only three quarters and gained 47 yards on 20 carries — his third consecutive sub-100 yard day.

Rookie Darryl Tapp sacked Manning for an 11-yard loss to end the Giants’ second drive. Burleson then made a twisting catch of a 12-yard throw for a 14-0 lead.

Manning’s next error was a looping toss intended for Amani Toomer, who was briefly open on a corner route. Hamlin, roving in the middle of the field, raced under the pass and returned his second interception of the period 26 yards to the New York 27.

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That became a 21-0 lead four plays later, when Hasselbeck found Jackson for an easy, 4-yard touchdown pass.

Just after Manning finally had positive passing yardage, early in the second quarter, Burress allowed a throw to clang off his hands and into the arms of Michael Boulware for another interception. The Seahawks converted that into a score when Heller ran past flat-footed R.W. McQuarters to become all alone for a 10-yard touchdown reception. That made it 28-0.

Jay Feely’s 46-yard field goal to end the half kept the Giants from a halftime shutout.

Manning threw scoring passes of 13 yards to Toomer and 25 yards to Tim Carter in the fourth quarter to make it 42-17. McQuarters then returned an interception 27 yards for another touchdown with 9:30 left.

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New York’s final score came on a 9-yard scoring pass to David Tyree with 2:42 remaining.

“Right now,” linebacker Antonio Pierce said entering New York’s bye week, “we’re a horrible team.”

Notes: Alexander’s touchdown gave him 102 for his career, most in Seattle history. Alexander has 91 career touchdowns rushing, tied for eighth in NFL history with Franco Harris and Jerome Bettis. ... Giants LB Carlos Emmons left with a pectoral strain and didn’t return.

NFL game stories Quick look at Week 4 games STEELERS 23, RAVENS 20, OT: Baltimore loses first game of season REDSKINS 26, COWBOYS 24: Dallas can't contain Portis in 1st loss BEARS 24, EAGLES 20: Goal-line stand boosts Chicago JETS 56, CARDINALS 35: Favre throws career-high 6 TDs BUCS 30, PACKERS 21: Ryan's 3 FGs lift Tampa CHARGERS 28, RAIDERS 18: San Diego tops rival 10th straight time BILLS 31, RAMS 14: Buffalo 4-0 for first time since 1992 CHIEFS 33, BRONCOS 19: Johnson rushes for 198 yards for K.C. BROWNS 20, BENGALS 12: Anderson throws TD TITANS 30, VIKINGS 17: Tennessee 4-0 for first time ever PANTHERS 24, FALCONS 9: Smith honors Lucas after TD JAGUARS 30, TEXANS 27, OT: Scobey kicks game winner SAINTS 31, 49ERS 17: McAlister scores first TD of year