By HOWARD BECK

ORLANDO, Fla. — The most captivating strand of the Jeremy Lin mystique is that he came from nowhere, emerging overnight to become a star, after being underestimated and overlooked, disregarded by college coaches, ignored in the N.B.A. draft and waived twice in two weeks.

The narrative is well-established, factual in its broadest strokes and altogether flawed, or at least woefully incomplete.

Jeremy Lin’s rise did not begin, as the world perceived it, with a 25-point explosion at Madison Square Garden on Feb. 4. It began with lonely 9 a.m. workouts in downtown Oakland in the fall of 2010; with shooting drills last summer on a backyard court in Burlingame, Calif.; and with muscle-building sessions at a Menlo Park fitness center.

It began with a reworked jump shot, a thicker frame, stronger legs, a sharper view of the court — enhancements that came gradually, subtly, through study and practice and hundreds of hours spent with assistant coaches, trainers and shooting instructors over 18 months.

Quite simply, the Jeremy Lin who revived the Knicks, stunned the N.B.A. and charmed the world — the one who is averaging 22.4 points and 8.8 assists as a starter — is not the Jeremy Lin who went undrafted out of Harvard in June 2010. He is not even the same Jeremy Lin who was cut by the Golden State Warriors on Dec. 9.

Beyond the mystique and the mania lies a more basic story — of perseverance, hard work and self-belief.

“He’s in a miracle moment, where everything has come together,” said Keith Smart, the Sacramento Kings coach, who was Lin’s coach with the Warriors last season.

Smart can hardly recognize his former pupil these days. Nor can Eric Musselman, who coached Lin in the N.B.A. Development League for 20 games. Nor can Lamar Reddicks, a former Harvard assistant coach, who fondly remembers a freshman-year Lin as “the weakest guy on the team.”

“I look at him on TV now,” Reddicks said, “and I’m like, I can’t imagine that he’s this big!”

What scouts saw in the spring of 2010 was a smart passer with a flawed jump shot and a thin frame, who might not have the strength and athleticism to defend, create his own shot or finish at the rim in the N.B.A. The evolution began from there.

Eager Learner

Lin earned a free-agent contract with the Warriors after a strong showing in the 2010 summer league, where he surprisingly outplayed John Wall, the No. 1 pick in the draft.

Smart, then an assistant under Don Nelson, noticed something in Lin’s first pickup game against the Warriors’ young stars, Stephen Curry and Monta Ellis.

“He’s getting to the paint,” Smart recalled. “You say, ‘Man, that’s a unique skill.’ Now he needs to pass the ball, as opposed to trying to get to the rim all the time.”

Soon, Smart noticed something else. Lin was the first player at the Warriors’ training center every day, eating breakfast by 8:30 a.m. “Then, all of sudden, you’d hear a ball bouncing on the floor,” Smart said. Practice typically began at noon.

Another assistant, Stephen Silas, began working daily with Lin, and provided him with a catalog of tapes showing elite point guards in the pick-and-roll: how they got into the lane, how they kept the defender on their hip, how they drew in the opposing big man to free up their pick-and-roll partner. Phoenix’s Steve Nash figured prominently. Silas and Lin worked on drills to give Lin other options, like a floater in the lane.

Then Lin would get into a game and try to use what he had learned. But he would over-penetrate and miss the open man.

“It wasn’t there yet,” Smart said.

As for his perimeter game, Smart said, “Jeremy couldn’t shoot at all.”

Lin had a habit then of pulling the ball behind his head and tucking his feet up under him — “like he was springing up off a trampoline,” Smart said.

Still, Lin kept arriving early, leaving late, devouring film and working studiously with Silas and later Lloyd Pierce. But what Lin really needed was game repetition. The Warriors sent him to Reno, their D-League affiliate, on three occasions. That is where the lessons started to take hold.

Stages of Growth

In Lin’s first D-League tour, the focus was primarily on developing his pick-and-roll game.

“He had no problems scoring for himself,” Musselman said. “It was more seeing the opposite side of the floor, and using the whole floor, instead of just the side the pick-and-roll was on. And he kept getting better and better at that.”

Having yet to harness his aggression, Lin got called for a lot of offensive fouls. Still, Musselman saw something special immediately, a quality that foretold possible greatness.

“I thought he was one of the best dribble-drive guys I ever coached, up there with Gilbert Arenas,” Musselman said. “Things you can’t teach.”

By Lin’s second tour, they were working on how to take a blow on the drive and still get off the shot. Musselman also introduced a middle pick-and-roll — one used frequently by Chris Paul in New Orleans — set just beyond halfcourt, in transition, to give the guard maximum room to drive.

“That was the point when we knew that he was a special player,” Musselman said. “Because the more wide open the floor was, the better he became.”

They also worked on how to read and attack defensive double-teams. On traps, Lin learned how to draw the opposing big man out and set him up before exploding past him.

By Lin’s third D-League tour, he had also smoothed out his jumper and become more confident in his 3-point shot, which Musselman said was “probably the most dramatic change.”

In 20 games, Lin averaged 18 points and 4.4 assists, while shooting .477 percent from the field and .389 from 3-point range. Throughout the experience, Lin urged Musselman to treat him like all of the other D-League players, and to push him just as hard.

Musselman noticed something else, too. As an N.B.A. player on assignment, Lin got first-class plane tickets. “He gave them to teammates,” Musselman said.

When Lin’s rookie season ended, the Warriors saw a player who might grow into a backup role behind Curry. They could not have foreseen the changes to come between July and December.

Beating the Ghost

Doc Scheppler has coached in Bay Area high schools for 34 years. He first saw Lin as a scrawny eighth-grader. But even then, “he had the ability to see the floor, make the right decision, make the correct angle pass. And that is just not done at 13, 14 years old.”

Last summer, Lin sought out Scheppler to help him with his 3-point shot. It was improving, but Lin was still shooting too high and throwing the ball — a “flying weapon,” Scheppler called it.

Working mostly in Scheppler’s backyard in Burlingame, Lin learned to begin his shot on the way up and release it at his peak. They also worked on a variety of in-game situations: the catch-and-shoot, off-the-dribble shots, and hesitation moves to create space.

Lin’s perfectionist tendencies came out in a 3-point-shooting drill called “beat the ghost,” in which Lin earned 1 point for every shot he made at the arc and the “ghost” earned 3 points for every shot Lin missed.

On one occasion, Lin made 17 3-pointers but lost 21-17, then kicked the ball in anger, Scheppler recalled with a chuckle. He refused to stop until he beat the ghost. It took 14 games. When Scheppler tallied up all of the scores for the day, Lin had converted 71 percent of his shots from the arc. “That’s the beauty of Jeremy Lin,” Scheppler said. “It’s not about moral victories. It’s ‘I have to win.’ ”

Yet an outside shot would not be enough. Lin needed to be able to consistently convert shots in the lane. And to do that, he needed to withstand the contact.

On Scheppler’s advice, Lin sought out Phil Wagner, a physician and trainer who owns Sparta Performance Science in Menlo Park. Wagner saw a player with enviable athleticism, but who lacked the explosiveness of an elite N.B.A. player.

“Most basketball players can create force very quickly,” Wagner said, referring to a player jumping off the floor. “Jeremy couldn’t.”

He compared Lin to a stretched-out rubber band — flexible, but lacking that snap-back quality. The goal was to make him “stiffer,” through a training program of heavy weights and low repetition, in conjunction with a high-protein diet. With the added muscle, Lin pushed his weight to 212 pounds from 200, while increasing his vertical leap by 3.5 inches, Wagner said. The result is evident every time Lin barrels into the lane this season.

“The biggest thing I see is when he gets intro traffic, he’s able to maintain his direction and his balance, because he’s stronger,” Wagner said, adding, “He’s a physical guard. That’s where I see his hard work and the program he did with us paying off.”

Wagner added: “Before, he was a motorcycle: he was maneuverable, but very off-balance. Now he’s like a Porsche: he’s fast, but he’s stable.”

Unfortunately for the Warriors, they hardly had a chance to assess Lin’s off-season transformation. The N.B.A. lockout prevented them from working with him until camps opened in early December. He was on the court for maybe 90 minutes before the Warriors cut him in a move to clear payroll room to chase a free-agent center.

Putting It All Together

The Knicks picked up Lin on Dec. 27, after training camps had ended, and after the Houston Rockets cut him, also for payroll reasons. The coaches were impressed with his solid 6-foot-3 frame and his athleticism. He instantly ranked among their top players in agility tests.

But the coaching staff had seen little of Lin since the spring of 2010, when they put him through a predraft workout. Because of the compressed schedule, practices were few. Lin was fourth on the point-guard depth chart.

Still, the same traits Lin showed in Golden State quickly emerged. He was the first to arrive every day, and the last to leave. He sought and devoured game tapes. When he requested his own clips, Lin asked to see his turnovers and missed jumpers, not his assists.

In side sessions with the assistant Kenny Atkinson, Lin kept working on his jump shot and his decision making in pick-and-roll situations. The coaches instantly recognized his ability to blow past defenders, but without much regard for what he would do once he beat them. So they worked on footwork, judgment and subtle movements to freeze a defender.

The work continued, quietly and without much notice, for five weeks, until Feb. 4, when 20 months of lessons coalesced into one eye-opening performance, and then a string of them.

“He has a tremendous capacity for processing information,” Smart said. “When you talk to him, he’s looking you in the eye and he’s analyzing the information. He’s putting them in the folder in his mind. Now he’s opening the folder and pulling the things that he needs.”

Now Lin is an entrenched starter for a quality team, with a jump shot that warrants respect and a passing touch on par with the league’s best. But the education continues. Teams are forcing Lin to go left, to his weaker hand. They are flustering him with multiple defenders. On Thursday, the Miami Heat held Lin to just 8 points and 3 assists, the worst performance of his otherwise-magical run.

The box score shows failure. To Lin, it reads like a teachable moment.

“I’m sure in the next couple weeks, someone’s going to figure out how to slow him down and stop him,” Reddicks said before the loss to the Heat. “It’s a chess match. He’s going to figure out how to beat that. That, to me, is a kind of a testament of who he is.”