As an 8-year-old, Jacoby Ellsbury was getting ready for the world of professional sports.

BOSTON —

As Jacoby Ellsbury walked toward the dugout at Fenway Park after shagging balls before Wednesday’s game, three children dressed head to toe in Red Sox gear and holding shiny new baseballs in the air called out to him from the front row of the stands:

“Ellsbury, can you sign a ball for us?”

A nearby security guard admonished them.

“You guys say, ‘Mr. Ellsbury.’ He’s in the big leagues now.”

Ellsbury didn’t say a word. He smiled as he signed his autograph for the kids.

The guard was right, with one clarification: Ellsbury, 24, isn’t just in the big leagues. He’s played his way onto one of baseball’s biggest stages, starting key games in the outfield for the playoff-bound Boston Red Sox.

“Everything has happened so quickly, I haven’t really had too much time to think about it,” Ellsbury said.

So far, he’s on his way. In a handful of games since being recalled from the minor leagues on Sept. 1, Ellsbury’s highlight reel of clutch hitting and otherworldly speed has made him a star overnight, in a town where baseball fever is an epidemic without a cure.

“There is a special electricity that goes through the stadium when people know he’s going to come to the plate,” said longtime Sox fan Al Chase, who ranked Ellsbury as the most exciting rookie he’d seen in decades of coming to Fenway Park.

“Red Sox Nation loves him.”

On Friday, against the New York Yankees, Ellsbury elicited a stadium-wide “ooooh” and standing ovation from the 36,590-person crowd with a second-inning single that squirted past the diving Yankees second-baseman and scored the game’s first run. Although the Yankees won 8-7, Ellsbury did his part, scoring a run, stealing second base with a head-first slide and chipping in two hits.

On Saturday, Ellsbury added two hits and three RBIs in Boston’s victory over New York, extending his hitting streak to 13 games.

Not bad for a kid from Madras.

Small-town stardom

Ellsbury was a star from the time he got to Madras High School, where he lettered in five sports: baseball, basketball, football, soccer and cross country.

His high school baseball coach, Bruce Reece, knew Ellsbury was different from his first practice as a freshman.

“From the time he stepped on the field to the time he got off, he was a very astute student of the game. He worked diligently every day,” said Reece, now athletic director at Oregon City High School. “We knew he was a heck of an athlete, and there was no doubt he was going to be really, really good.”

Ellsbury’s parents, Jim and Margie, lived on the Warm Springs Indian Reservation until he was in kindergarten. Margie, who is part Navajo, said she came to Warm Springs in 1980, after her sister married a tribal member there. She now works for the tribes in the early-childhood education department, while Jim is a forester for the Bureau of Indian Affairs.

Even as a child, Ellsbury was strengthening the legs that would make him stand out on the Major League stage, by pedaling his plastic tricycle in front of the house in Warm Springs, Margie said.

“He would go up and down the sidewalk and just push those legs up and down,” she said.

The family moved to Madras halfway through Ellsbury’s kindergarten year, Margie said, and except for one year in Arizona, stayed there.

Since he was a child, Ellsbury wanted to play pro sports. He was still young when he set his sights on baseball, Margie said.

“I always remember his dad saying, ‘You probably won’t grow very tall, so forget about being a pro basketball player.”

Today, Ellsbury looks a little shorter than his listed height of 6 feet, 1 inch and is well-built at 185 pounds. His dark hair and square jaw have drawn frequent comparisons to New York Yankees center fielder Johnny Damon.

“I don’t mind them at all,” Ellsbury said of the comparisons. “I think it’s a great compliment to me, but at the same time, I try to be my own player. I pretty much just try to develop my own game and develop my own skills to the maximum of my own potential.”

A matter of time

Ellsbury got his first taste of the majors earlier this summer, when he played in six games in June and July before being sent back to the team’s AAA club, the Pawtucket Red Sox. He played one game in August, but came back to the bigs, likely for good, on Sept. 1, after two minor league seasons.

His parents and three younger brothers traveled to Rhode Island on Aug. 28 to watch three of his games with Pawtucket. Then they made the trip to Boston for three games after he was called up.

In the second game, with his parents watching from the stands, Ellsbury hit his first Major League home run.

“The second day was when Jacoby had his home run, and we were all giving each other high fives and then I was really excited and happy and then I started getting emotional,” Margie said.

Margie was so overwhelmed, she was wiping away tears by the time he finished his home run trot.

“I didn’t even get to see him cross home plate,” Margie Ellsbury said.

Ellsbury hasn’t let up since. In his first 20 games with the Red Sox Ellsbury earned New England’s love by batting .394, with three home runs, five stolen bases and four doubles. But he’s not satisfied. Ellsbury said he wants to establish himself as one of the best players in the league.

“I see myself as an All-Star-type player,” Ellsbury said of his potential.

He’s not the only one. Ellsbury could come with a power cord, if the Boston fans and media who fixed on “electric” as the defining adjective for his well-balanced game are to be believed.

On July 2, Ellsbury earned his electric label by scoring from second on a wild pitch, a rare play, since the player on second usually has to run about twice as far.

In the fourth inning of a game against the Texas Rangers, Ellsbury reached second on a single and a steal. As pitcher Brandon McCarthy went into his windup, Ellsbury took two springy sideways steps toward third, like a charge of electricity trapped behind a light switch. As the pitch bounced in front of home plate, Ellsbury paused for an instant, planting his left foot. When the ball caromed sideways off of the catcher’s glove toward third base, the switch flipped on, and Ellsbury took off.

He’s so fast, he reached third before his coach had time to signal whether to hold up or continue. He’s so fast, he rounded third and was only a few yards from home plate before the catcher arrived at the ball. He seemed to pick up speed until the instant he slid home, just ahead of the catcher’s throw, then bounced back up in a single motion. All in eight seconds.

Ellsbury’s celebration: A slight touch of his helmet and tug of his jersey while walking calmly back to the dugout. Red Sox veterans said they had seldom seen such a display of raw speed and killer instinct.

That instinct is what sets Ellsbury apart, said Pat Casey, Ellsbury’s coach for three years at Oregon State University.

“There are guys who maybe have as much speed as Jacoby has, but when you add that to instinct, he not only is fast, but intuitively he is a great baseball player,” Casey said. “Those are special guys.”

Ellsbury’s success was no surprise to pitcher Clay Buchholz, a fellow Red Sox rookie who has also experienced rapid fame after throwing a no-hitter in his second Major League start.

“I knew it was only a matter of time,” Buchholz said, before Ellsbury became a star.

In person, Ellsbury comes across as quiet and confident; he rarely volunteers information about himself, but answers questions thoughtfully and directly. His dad said that’s who Ellsbury is, intense, but “not a yeller or something.”

Casey said he expects Ellsbury to show more of himself as he acclimates to the majors.

“I just think that he’s going to be a little bit reserved at first and then get a little more comfortable with his surroundings,” Casey said. “I think Jack’s personality is tremendous.”

His poise stands out to Red Sox infielder Royce Clayton, veteran of 17 Major League seasons.

“This is a big stage to be coming up on,” Clayton said. “He’s done a good job, and he’s working on his game and being focused and not being intimidated by the atmosphere.”

On game days, Ellsbury’s routine is set: He eats a filling breakfast — “an omelet, pancakes, that sort of thing” — after he wakes up at about 11 a.m. He gets to the ballpark by 1 p.m., where the first thing he does is check the lineup to see if he’s starting. Then, he eats lunch.

This time of year, late in the season, Ellsbury will go to the whirlpool and stretch before getting in some light weightlifting and a little time on the exercise bike.

“Nothing big, just kind of maintenance this time of season,” he said.

After early hitting work and batting practice, Ellsbury eats again, this time a lighter meal, like a grilled cheese sandwich with a side of yogurt and fruit. He’ll take time to review notes about the pitcher and watch film, then get dressed, take a shower and stretch one more time before the first pitch at 7 p.m.

Adjusting to the big leagues hasn’t left a lot of time for extracurricular activities, according to Ellsbury and Buchholz, who were roommates at Boston’s Minor League team in Pawtucket.

“We go out every now and then, have a couple of drinks, take the edge off,” Buchholz said.

But mostly, there’s not a lot of time to socialize while acclimating to a Major League schedule, both said.

On Thursday, their first day off since being called up on Sept. 1, the pair moved into an apartment in Boston, replacing the hotel rooms that served as home since the beginning of the month.

The apartment is “very expensive,” according to Ellsbury’s dad. It’s one of a few big-ticket items Ellsbury has bought since signing a $1.5 million bonus with the Red Sox two years ago.

Ellsbury said he invested much of his windfall, but first he bought a new house in Madras for his mom, Margie. Then came a condo in Tempe, Ariz., and an almost-new Cadillac Escalade, currently parked in Mom’s garage.

He also likes nice clothes, Jim Ellsbury said. And whenever he buys new threads, he gives his old stuff to his brothers or dad, all of whom have the same shoe size.

“I don’t buy shoes any more,” Jim said.

Fame

Meanwhile, in Boston, Ellsbury’s fame continues to grow. People recognize him on the street now, and a throng of reporters gathered at his locker Wednesday, even though he wasn’t scheduled to play.

“I was actually at a car dealership (Thursday), and people came up and asked for an autograph,” Ellsbury said Friday. “Its pretty fun. I don’t mind it too much.”

Meanwhile, Boston’s Internet fan base has started a debate on what nickname to bestow upon their new outfielder. One Web site, riffing on his electric play, suggested “spark.”

At Oregon State University, Casey said, they called him Jack, or Jackaby.

“We called him Jackaby; it kind of tied into his ability to run like a jackrabbit,” Casey said.

Ellsbury said he’ll take whatever nickname fans give him.

“Nicknames are better if someone else gives them to you than if you come up with one yourself,” he said.

For now, at least at Fenway Park, call him Mr. Ellsbury.