New Jets coach Eric Mangini decided yesterday to keep offensive coordinator Mike Heimerdinger on staff, shortly after parting ways with defensive coordinator Donnie Henderson.

The move to retain Heimerdinger came as a mild surprise, since he and Manigni have no history together. But having Heimerdinger around should make things easier on offense, since he has been with the team for only one season.

Many thought Heimerdinger would be let go, and were linking him to jobs in Denver and Houston. But now he gets another shot to help an offense that struggled mightily in 2005 without starting quarterback Chad Pennington or starting running back Curtis Martin.

It also makes sense to keep Heimerdinger so he can have more time with work with Pennington, who is coming off his second major shoulder injury.

Heimerdinger said his meeting with Mangini went well and he was impressed with his energy. He said it didn’t make a difference that he would be working for someone so much younger. Mangini turned 35 yesterday.

“His experience is good, age doesn’t make a difference,” Heimerdinger said.

Henderson, receivers coach Pep Hamilton, and tight ends coach John Zernhelt weren’t retained. It was widely expected that Henderson would be let go.

When reached on his cell phone, Henderson declined comment. Linebackers coach Bob Sutton will be promoted to defensive coordinator to replace Henderson, a person familiar with the decision said last night. The source declined to be identified because an official announcement had not been made.

Team spokesman Ron Colangelo declined comment.

Sutton, 54, coached the Jets linebackers for the last six seasons. He was Army head coach from 1991-1999, and before that was defensive coordinator for the Black Knights from 1983-90.

Henderson joined the Jets for the 2004 season, overseeing a vast improvement in the defense as the Jets made the playoffs.In 2005,the defense played well in spots, but could not carry an anemic offense. Injuries also plagued the team as the Jets finished 4-12.

Hired by previous coach Herman Edwards,who left earlier this month to become Kansas City’s coach, Henderson guided a unit that ranked second against the pass, mainly because opponents could run so well against New York.The Jets were ranked 29th at stopping the run.

Hamilton joined the coaching staff in 2003, when he was hired as offensive quality control coach.After that season he was elevated to offensive assistant coach before being promoted to oversee the wide receivers in 2005.

Zernhelt joined the Jets last February. He’s a former head coach at The Citadel.The fate of special teams coordinator Mike Westhoff was still up in the air. Heimerdinger, Henderson, and Westhoff interviewed for the job that went to Mangini.

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TWO SEAHAWKS MISS PRACTICE

Wide receivers Darrell Jackson and Bobby Engram, and defensive tackle Rocky Bernard all missed a second straight day of practice for the Seattle Seahawks yesterday.

Coach Mike Holmgren was optimistic that all three could practice some, but none of them participated in team drills. All three are listed as questionable on the injury report for Sunday’s NFC championship against Carolina.

Jackson is still recovering from Oct.12 surgery on his right knee, but also has a back bruise from a block in last week’s win over Washington. He briefly left the game, but returned and finished with nine catches for 143 yards and a touchdown in the win over the Redskins.

Engram also has a sore back and Bernard has a left foot injury. Engram had two catches against Washington and Bernard had two tackles. Bernard had a career-high 8 1/2 sacks for Seattle this season, which led the NFL with 50 in the regular season.

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NFL APPROVES 48 UNDERCLASSMEN

Reggie Bush and Vince Young were among 48 underclassmen approved yesterday by the NFL to enter the draft.

USC’s Bush, the AP Player of the Year and Heisman Trophy winner, and Young, who led Texas to the national championship, are expected to go early in the first round on April 29.

Four of Bush’s teammates – running back LenDale White, defensive back Darnell Bing, tackle Winston Justice, and guard Fred Matua – also left school early for the NFL.

Other notables who declared for the draft were North Carolina State defensive end Mario Williams; running backs Maurice Drew of UCLA, Brian Calhoun of Wisconsin, and Laurence Maroney of Minnesota; and wide receiver Santonio Holmes of Ohio State.