NEW YORK – Patrick Ewing retired from the NBA on Tuesday, ending the 17-year career of one of the league’s greatest centers but leaving him short of his repeated promise to win a championship.

Ewing, an 11-time All-Star who was chosen as one of the 50 best players in league history, spent 15 years with the New York Knicks, averaging 22.8 points and 10.4 rebounds. He was traded to Seattle before the 2000 season and then signed as a free agent with Orlando last year.

The 40-year-old center finishes his NBA career with 24,815 points and 11,606 rebounds.

“It’s time to move on,” Ewing said at a news conference. “It was a great ride.

“I’m disappointed that I never won a championship – in the pros, I’ve got to add that. But I’m at peace.”

Ewing said he has been hired as an assistant coach with the Washington Wizards, meaning he will be on a team with the player who often denied him his shot at an NBA title: Michael Jordan.

Jordan led to the Chicago Bulls to six championships, knocking off the Knicks in the playoffs in four of those seasons.

“Instead of needling me from afar, he’ll be needling me in the same town. We’ll be in the same organization,” Ewing said.

Several of Ewing’s former teammates attended the news conference at a midtown Manhattan hotel, including former Knicks forward Charles Oakley.

“We had some battles, didn’t we Oak?” Ewing shouted out to Oakley from the podium.

Also at the announcement were former Knicks teammates Charlie Ward, Allan Houston and Mark Jackson, who was traded to the Denver Nuggets in June. Alonzo Mourning, sidelined this season with the Miami Heat because of a kidney condition, attended along with Ewing’s high school coach, Mike Jarvis, and Jeff Van Gundy, his longtime coach with the Knicks.

“He was a role model even then,” said Jarvis, now the coach at St. John’s.

“He competed hard every night out,” Houston added.

Ewing said he wanted to be remembered as a player with “a hard head, a hard nose, the work ethic that I brought.”

The No. 1 pick in the first NBA lottery draft in 1985, the 7-foot Ewing came out of Georgetown to become the Knicks all-time leading scorer with 23,665 points, but he never won the championship he guaranteed.

“There are many great players who have never won a championship,” he said.

Ewing did help Georgetown reach the NCAA championship game three times, winning the national title in 1984.

In 1994, Ewing was the centerpiece of the Pat Riley-coached New York team that lost in the NBA Finals in seven games to the Houston Rockets after taking a 3-2 lead in the series. Ewing was injured in 1999 when the team lost in the finals in five games to the San Antonio Spurs.

Ewing also is the Knicks’ all-time leader in rebounds (10,759), steals (1,061), blocked shots (2,758), games (1,039), field goals made (9,260), field goals attempted (18,224), free throws made (5,126) and free throws attempted (6,904).