SAN JOSE -- The Earthquakes signed their first Homegrown Player, 18-year-old Tommy Thompson, on Wednesday.

A speedy attacking midfielder, Thompson, a Loomis native who has trained in the Quakes' youth development program, will forgo his final three years at Indiana to compete in MLS.

Quakes general manager John Doyle introduced Thompson during a ceremony on the grounds of the club's new stadium, which is scheduled to open in 2015 and is located across the street from Mineta San Jose International Airport.

Doyle discovered Thompson about four years ago at a club game in Sacramento.

"I think he created 10 chances, ran by players, scored a couple goals, and I thought, man, this is a real kid that can make it," Doyle said.

It's been a whirlwind rise for Thompson, who graduated from Granite Bay High a year early to attend Indiana. Now he's trying to find an apartment in San Jose.

"There really isn't a better time to come into San Jose," Thompson said. "This stadium is exciting. Just being here makes me even more excited. It's kind of been a whirlwind signing so quickly, but I can't wait to get started and hopefully have an impact as soon as possible."

The Quakes are the last team in MLS to have a homegrown signing, which does not work against a club's salary cap. Per MLS rules, a club may sign a player to his first professional contract without subjecting him to the MLS SuperDraft if the player has trained for at least one year in the club's youth development program and has met the League's Homegrown Player criteria. Players joining MLS through this mechanism are known as Homegrown Players.

The Quakes don't necessarily expect Thompson to contribute right away but aren't ruling it out. Thompson said the Quakes made him a contract offer before he left for college, and final negotiations came in December. Terms of the agreement were not announced.

"Going back to Indiana was a possibility," Thompson said. "It was my dream to sign with San Jose, but Indiana is a great place for development as well."

After discovering him as a teenager, the Quakes recruited Thompson into their academy program, where his stock continued to grow. Last year before heading off to Indiana, Thompson played for the Quakes' Reserve League squad, when he had four assists in five appearances. He also turned heads in training against senior-level players such as center back Victor Bernardez.

"It made more it comfortable signing at an early age," Thompson said of his Quakes' experience. "I met some of the guys, they were great to me as a high-schooler. So it just made the transition a lot less scary. I went into the locker room yesterday and was greeted with handshakes and hugs, and it just made me feel right at home."

Quakes coach Mark Watson said Thompson is proof that there are good players in the area, "which is going to be the lifeblood of our organization."

Thompson is part of an impressive soccer family -- his brother Ty played as a sophomore at Stanford last season, and brother Tanner was Tommy's teammate as a fellow freshman at Indiana. Thompson's dad Gregg Thompson starred at Indiana before playing professionally and with the U.S. national and Olympic teams.

Gregg Thompson describes Tommy as a mature kid who passed on some high-school experiences to pursue his dream.

"He graduated high school a year early to get to Indiana because he wanted to pursue soccer as soon as he could," Gregg Thompson said at Wednesday's event. "This opportunity with going pro so quickly caught us off-guard a little bit. We talked quite a bit about that. On the field is where most of his maturity is. He still has to keep track of how to wash his dirty clothes and everything."

Tommy Thompson says playing spirited 2-on-2 games with his siblings and his dad helped sharpen his game.

"It'd get chippy," he said. "That's where I got some of my edge as a player."

Tommy missed six matches because of a knee injury last season, but was chosen Big Ten Freshman of the Year and made the Soccer America freshman All-America team. He tied for the team lead in goals (five) and total points (13). He said his success at Indiana convinced him he was ready for MLS.