As first impressions go, Eiichi Jumawan was hardly impressed when a scrawny Colleen Loo enrolled at his PearlSide Boxing Club in Pearl City four years ago. He's since changed his tune.

"I thought she just wanted to get in shape," recalled Jumawan of the 5-foot-1 1/2, 100-pound Loo. "Little did I know, this skinny girl had a desire to compete."

Loo, 19, has shown amazing winning spirit and persistence, and is currently No. 2 in the USA Boxing's pinweight (101 pounds) first-quarter rankings. Loo is poised to get the top spot in the new amateur rankings because No. 1 Chantel Cordova, of Pueblo, Colo., turned professional in March, Jumawan said.

"It feels good, but I have to work and train hard," said Loo, who won the National Golden Gloves and National PAL women's titles in 2005, along with a bronze medal at the U.S. Championships. This year, she won silver at the U.S. Championships. "I want to show everyone that I'm good enough to be in that spot."

This month, Loo will become the first Hawai'i female boxer to represent the United States in the 2006 Pan Am Games, which began yesterday and goes through June 5 in Buenos Aires, Argentina, Jumawan said.

"If the average athlete had her desire and work ethic, they would all be world champions," Jumawan said of Loo, who trains seven days a week, sometimes twice a day. "That's the reason why she's so good."

Loo sought boxing as a stress-reliever after the death of her surfing chaperone and father, Peter-James, in December 2001. Earlier, she tried out for the Mililani High School basketball team, but was cut.

Burdened by school and life, Loo said, "plenty of times, I wanted to hit something, but I couldn't hit the door. I couldn't hit the wall."

Loo's mother, Michele, knew PearlSide assistant boxing coach Don Casil, and eventually Loo started with the boxing club in 2002.

"When she first came to us, I looked at her, and thought, 'She's kind of off-balance, she has no rhythm, she has no strength,' " said Jumawan, who won national AAU titles in 1975 and 1978, and went 9-0 as a professional boxer. "She came out one day, and said she wanted to compete, and then she wanted to spar with the boys. She was so tiny, she would get beat to the punch. She was so light, she couldn't keep up with the kids. But she kept coming."

Determined to increase her strength, Loo joined 24 Hour Fitness on her own, and befriended the staff who tailored a weight training program to complement her boxing.

In addition to her running program, Loo watches hours of boxing videotapes, searches the Internet for boxing training tips, attends Leeward Community College and works at the Tony Group's Autoplex Car Wash in Waipi'o.

And since PearlSide Boxing Club does not have a boxing ring, Loo travels to other clubs, such as Wahiawa's boxing gym, to spar with boys mostly.

"They help me out, too," Loo said of the Wahiawa coaches. "I don't mind sparring with the boys. They naturally hit harder, so when you get hit by girls, they don't really hurt me — for the most part."

Earlier, Loo and her mother paid for some of her boxing trips to the Mainland when the boxing club couldn't cover the costs. Loo has since secured several sponsors, her coaches said.

With her accomplishments and work ethic, Loo has become a role model at the PearlSide Boxing Club.

"She's a good inspiration," said 12-year-old Selena Ryder, a Mililani Middle School seventh-grader, who joined the club three years ago. "She's really nice. She helps a lot with coaching, and she's like a big leader to us. I want to be like her when I grow up."

Sparring partner Keanu Sabado, 13, said Loo sets a good example.

"Yesterday, she came to practice in just her natural clothes and her gloves," said Sabado, an 'Aiea Intermediate eighth-grader. "That shows me she's really dedicated to what she does. She comes straight from work, goes home, and watches her little sister. That's a real hard worker."

"After practices, she goes to the gym and works out there," added Kurtis Hagi, 13, an eighth-grader at Highlands Intermediate. "After practice, I usually just go home and eat food."

In the past several years, enrollment at PearlSide Boxing Club has grown from about six to 60 boxers, Casil said. The club has about 10 female fighters, he said.

"On the Mainland, women's boxing is very big," Casil said. "They have fights almost every weekend in connection with the men's fights."

Loo said she works hard, in part, to "prove women's boxing can be just as popular as the men." Her goal is to make the 2012 Olympics. Afterward, she wants to coach and help promote women's boxing.

"I want to show women can be just as good as the men, maybe even better," she said.

At a recent practice, Loo said she was proud of the female boxers at the club.

"Even for these girls, it's good," Loo said. "They may not want to fight, but just to get them involved. You don't have to be a tomboy.

"You'd be surprised, a lot of the other fighters on the Mainland, a lot of them you wouldn't expect to be boxing. They look so pretty, like models. And you think, 'They're going to fight?' You see them coming out with black eyes and stuff, and you think, 'Geez.' But it makes it fun. It just shows if you want to, you can. There's nothing holding you back."

Reach Brandon Masuoka at bmasuoka@honoluluadvertiser.com.