Jeremy Lin played high school basketball in a gymnasium across the street from the Stanford campus. But the coaches there did not seriously recruit him. Neither did the coaches from UCLA. The same for the coaches from many Ivy League universities.

“We all felt the same way: We could get better,” said Steve Donahue, the former coach at Cornell.

The story of Lin’s college recruitment illustrates how talent evaluators overlooked his ability even when Lin was young. It is something that was repeated in the professional ranks as he moved from Golden State to Houston to New York, where he has infected Knicks fans with Linsanity, becoming a sensation over five transcendent games.

Lin has scored at least 20 points in five straight games before Tuesday night, all of them Knicks victories, becoming an instant fan favorite. He is also the first NBA player to have at least 20 points and seven assists in his first four starts.

“I don’t think anybody expected this to happen the way it happened,” said Lin, who helped carry the Knicks with stars Carmelo Anthony and Amare Stoudemire sidelined. Knicks coach Mike D’Antoni’s search for a point guard had been frustrated by injury and poor performances since waiving Chauncey Billups.

“He’s an underdog who came on, does it right, the right way,” D’Antoni said.

Lin helped the Minnesota Timberwolves draw their largest crowd since 2004 on Saturday. Sales of all merchandise at the Knicks’ official online store and Facebook page have risen more than 3,000 percent in the past week, said Delivery Agent, which runs the online store. Some items, like the Lin replica home jersey, are sold out. CNBC reported that web traffic to NYKnicks.com increased 550 percent last week.

Shares of Madison Square Garden Co., which owns the Knicks, the arena where they play and the cable network that broadcasts their games, rose 3.8 percent Monday to a record-high $32.32 because of the sudden emergence of Lin, analysts said. Three times the average number of shares were traded

The unassuming guard was asked if it’s difficult to focus on basketball with all the distractions.

“I try to just not pay attention to it as much as possible, spending a lot of time with my family and friends in my free time,” Lin said. “When I’m with the team we stay focused, and we know what we have to do. And then just staying in my Bible, basically.”

His NBA success would have been hard for some college coaches to have predicted while watching film of Lin as a skinny, average-shooting guard at Palo Alto High School, even though he was a standout for the modest program, leading it to a 32-1 record and an upset of the powerhouse Mater Dei in the 2006 state championship game.

“He was a good student, a good player and, yeah, it’s amazing what he was doing,” Donahue, now the coach at Boston College, said in a recent telephone interview. “But he didn’t look that athletic, and he didn’t shoot it all that well. Even after his freshman year at Harvard, you didn’t give it a second thought that we made a mistake.”

It was not that college coaches were entirely unaware of Lin. On the contrary, Lin sent film of himself to programs in the Ivy and the Patriot Leagues. But he has said that only Harvard and Brown showed serious interest in him.

Some coaches have wondered whether Lin, who is of Taiwanese descent, did not receive a closer look by recruiters because of his ethnicity. Coaches have said recruiters, in the age of who-does-he-remind-you-of evaluations, simply lacked a frame of reference for such an Asian-American talent.

Another big reason for the lack of interest might have been because Lin never possessed jump-out-of-the-gym athleticism. That made it hard for recruiters to pick up on his quick first step, his passing skills or his uncanny sense for the game simply from watching him at an Amateur Athletic Union tournament or in a high school playoff game.

“I just think in order for someone to understand my game,” Lin said in 2010, “they have to watch me more than once, because I’m not going to do anything that’s extra flashy or freakishly athletic.”

However, even for some college coaches who liked Lin’s game enough to speak with him about playing at their school, the notion of seriously pursuing him was not a consideration. No Division I school offered Lin a scholarship, but he discussed walking on at Stanford, California or UCLA with the coaches there.

“I said, ‘We can’t give you a scholarship right away,’” said Kerry Keating, a former UCLA assistant coach who spoke to Lin after watching him in a high school game. “I thought he could have played for us. He certainly could have made an impact for us, looking back on it. But at the time, you never really know. It’s an inexact science.”

Lin first got on the radar of the Harvard coaches before his senior year in high school. He had sent his material to them during his junior year, and they were able to watch him in person for the first time at an AAU tournament the next summer in Las Vegas.

The Harvard coaches’ initial impression of Lin was similar to that of the Ivy League coaches: nice player, but too slight for their liking. Lin was perhaps 6-foot-1 and weighed no more than 170 pounds. The first time Lin played before his future Harvard coaches, in Las Vegas, he did little to reveal the NBA potential within.

“He didn’t really stand out,” said Bill Holden, the former Harvard assistant coach who was responsible for recruiting Lin. “He was like any other average high school players we might see. When I saw his coach, I recommended he go to a Division III school.”

A few weeks later, Holden stumbled upon Lin at another AAU tournament. This time was different. Lin was playing against top-flight Division I recruits, and he was getting the better of them. Another Harvard assistant coach at the time, Lamar Reddicks, also liked what he saw in Lin when he compared notes with Holden after that tournament.

Lin suddenly became Harvard’s top recruit.

The Harvard coaches privately worried that Stanford, which could not help monitoring Lin because he lived and played so close by, would offer him a scholarship during his senior year. Their anxiety was heightened after Lin scored 17 points – and made a crucial 25-foot bank shot with just over two minutes left – to lead Palo Alto to a stunning 51-47 victory over Mater Dei. Yet Stanford did not increase its pursuit. And Lin picked Harvard.

“We were just happy we were getting our top guard,” Holden said. “We thought we were getting a nice future Ivy League prospect. But if I told any other guys on the team that Jeremy’s someday going to play in the NBA, none of them would have believed that.”

The Associated Press contributed to this report.