It began with a promise.

Twelve years ago, Lamar Odom’s elderly grandmother asked Jerry DeGregorio to promise her something. She said how Lamar didn’t have a mother, didn’t have a father, didn’t have any brothers and sisters, and she wanted one thing from DeGregorio.

“She asked me to promise her that I always — no matter what — would watch over him, take care of him and always be there for him,” he says.

That was when they both were at URI, DiGregorio as Jim Harrick’s assistant and Odom trying to salvage his basketball life.

Back when he once said, “I was as lost as lost could be.”

Already, they had a bond, one that began when DeGregorio first met Odom at a summer basketball camp in New Jersey before Lamar’s senior year in high school. Back before Lamar became the poster child for the cesspool that is big-time college basketball recruiting, back before his two years at URI, back before he became the fourth pick in the ’99 NBA Draft, back before all the money and fame that comes with playing for the world-champion Lakers.

And certainly back before he married reality TV star Khloe Kardashian five weeks ago in a celebrity wedding, one that went out over the tabloids like a roar of thunder.

But from the beginning they had a connection.

The black high school kid from Queens whose mother had died when he was 12 years old and whose father was a heroin addict. Lamar lived with his elderly grandmother in a tiny row house about a jump shot away from Aqueduct Race Track.

The white high school coach in Connecticut who spent his summers on the AAU basketball circuit.

Several months later, having left Christ the King High School in Queens and having spent time at a joke of a school in upstate New York, Odom was about ready to sink into the sewer of big-time basketball culture.

DeGregorio threw him a life raft.

Odom went to live with DeGregorio in Connecticut, and finished high school where DeGregorio taught.

We all know the rest of the story, or at least the broad-brush strokes. How he went to UNLV but never played because the NCAA was questioning his test score, and that he supposedly had taken some money from a booster. How he landed at URI in the fall of ’97 because DeGregorio had become an assistant for new coach Jim Harrick.

That’s the backstory, a one-paragraph summary of what arguably was the most bizarre time in URI basketball history.

What it doesn’t say, though, is their bond continued, even when Odom went off to the riches of the NBA and DeGregorio stayed behind in his two ill-fated years as URI’s coach.

What it also doesn’t say is that through all the years, DeGregorio has tried to live up to the promise he had made to Odom’s grandmother.

It hasn’t always been the easiest thing to do.

Maybe no one could have made up Odom’s story, and in a sense it belongs to us, for we saw it develop. Lamar at URI was almost an apparition — here one minute, gone the next — but there was never any question about his ability. It was all there in his one year as a player at URI — his versatility, his unselfishness and his great size.

The off-the-court stuff was always more difficult. He violated the league’s anti-drug policy twice in his first eight months. One of his sons died at six months old. His grandmother died.

But he is nothing if not a survivor.

This is now his 11th year in the NBA, a key ingredient on the championship Lakers, a great complementary player. He’s become one of the most popular Lakers, admired for his spirit, unselfishness and the fact he’s a great teammate.

Not that we should be surprised.

There always was a certain gentleness about Lamar in his time at URI, the sense that he wanted to be liked.

But here it is 11 years later and he has succeeded in ways that DeGregorio could only have envisioned back when Odom first came to Kingston “as lost as lost can be.” He turned 30 on Friday, no longer the kid he was back when DeGregorio was his life raft, perhaps the one man in the world he could fully depend on, the one person who always was there, even in the bad times.

“I always wanted Lamar to be happy, to live the life he wanted,” DeGregorio says.

DeGregorio lives in Santa Monica, works out about a dozen NBA players. He goes to about 50 Lakers games a year, sitting in the front row behind the basket in the Staples Center with Lamar’s two kids, for whom he’s the godfather. He’s also taking graduate courses. In the spring, he’s got a video coming out on basketball techniques.

“I’ve never been happier,” he says. “I’m a basketball coach and I get to work with the best players in the world.”

Five weeks ago, he was the best man at Lamar’s wedding. It was at the home of a producer in Beverly Hills, the celebrity marriage of the moment. Bruce Jenner walked his stepdaughter Khloe Kardashian down the aisle. DeGregorio sat at a table with Kobe Bryant. It all must have seemed a long way from Keaney Gym.

And he gave a speech.

He said how 12 years ago Lamar’s grandmother had asked for his promise, and how for the last 12 years, through all the joy and pain, through all the good times and the bad, he has tried to honor that promise.

And when he was finished, and the tears were running down Odom’s face, they hugged.

Hugged as father and son.

Hugged through history and love and dreams that came true.

And for a promise kept.