The thought of a promising career didn't creep into Gao's mind until about 2007. That year -- his second in the Mariners organization -- he batted .288 with 32 stolen bases for the Class A Wisconsin Timber Rattlers of the Midwest League.
"It took a while for me to think that I can make it to the Major Leagues," Gao said through interpreter Richard Wang of the Chinese Professional Baseball League. "It wasn't until 2007 that I started to feel I had a chance to play in the Majors."
Gao, an outfielder, proceeded through the typical ups and downs a Minor League career often presents. He posted a .277 average with 14 homers and 70 RBIs in 99 games at Class A High Desert in 2009 but struggled in multiple tours at Double-A in the following years.
Still, his talent was unquestioned. He had a future in baseball if he could harness it.
"I really enjoyed having Kuo Hui on the team," said Jim Pankovits, manager of the Double-A Jackson Generals. "He played and worked extremely hard, and was very successful when he was healthy and playing regularly. With his work ethic and upbeat personality, he has a very promising future."
But the most painful experience of Gao's life might have made that future obsolete.
During an international All-Star Series game between Chinese Taipei and Major League Baseball in his native Taiwan last November, Gao attempted to score on a base hit to right field. When he rounded third and sprinted toward the plate, however, the catcher was already in position to receive a throw from Josh Reddick and apply the tag.
"In that moment I was trying to avoid the collision, and I didn't adjust my pace right," Gao said. "Then I felt that my spike was stuck in the dirt and boom, it happened."
All of the progress Gao had made during his six-year climb through the Mariners' farm system crumbled, just like his lower limb. He dislocated his right ankle and fractured his leg. In a mere instant, countless thoughts funneled through his mind.
"First it hurt," he said. "Then I thought it might be broken. Then I thought that my baseball career was over."
Trainers removed Gao from the field on a stretcher and transported him to a hospital to undergo surgery.
"It's sad to see the way that happened, with a guy playing the game like it should be played -- 100 percent," Reddick said.
Giants skipper Bruce Bochy, who was managing the MLB team, called the ugly scene a "tragedy," and said, even after his club's victory, it "takes away a little bit from a good ballgame."
One year has elapsed. But for Gao, the 12 months of recovery have seemed more like 12 years.
"I felt lost," he said. "I was only able to watch my teammates play, watching them doing everything I want to do but cannot. It was somewhat lonely."
The Chinese Taipei team omitted Gao from its roster for this month's World Baseball Classic qualifiers but invited the 27-year-old to train with the club. Should he demonstrate that he has rounded into form after a year off, he could join the team in March if it advances.
"I am really motivated, and I really look forward to it," Gao said. "It's been a year [that] I have sat out of the game, and I actually did not expect to be called back to Taiwan and to train with the national team at this stage. I am very happy and grateful to have this opportunity."
Gao also plans to participate in a Taiwanese winter league. Though he remains ripe with ambition, his Major League aspirations are on hold until he can prove that his ankle and leg are at full strength. He is a free agent, although the Mariners would consider retaining him if he is healthy.
Gwynn didn't know much about Gao a year ago, but he has learned plenty about his drive to recover and resurrect his career.
"The first thing I think is, 'How are they going to react?'" Gwynn said. "You find out a lot about [a player's] personality in how he rehabs and is able to come back. Hopefully, it'll just be a bump in the road and he'll get back on the trail he was on."