10:56 AM PT -- Officials say Drew Gordon was driving a three-wheel Vanderhall Carmel when he crashed with a GMC Sierra pickup around 1 PM on Thursday.

Gordon died at the scene, while the 25-year-old driver of the GMC and a passenger were taken to a local hospital with non-life-threatening injuries.

Officials say the preliminary investigation indicates Gordon's vehicle crossed the center line and made contact with the GMC ... and impairment does not appear to have played a role in the accident.

Former NBA player Drew Gordon -- the brother of Denver Nuggets star Aaron Gordon -- died in a car accident in Portland on Thursday. He was just 33 years old.

Gordon was a star athlete growing up in California ... earning All-American honors at Archbishop Mitty High School in San Jose.

He went on to play college ball at UCLA and the University of New Mexico for two seasons each ... and later signed with numerous professional clubs in Europe, before making his NBA debut with the Philadelphia 76ers in November 2014.

He made nine appearances for the Sixers ... and continued his career in the G League and overseas until his retirement from the sport last year.

Gordon played in countries like Turkey, Serbia, Lithuania, France and Russia ... making All-Star appearances among other accolades.

28-year-old Aaron has not publicly addressed the loss ... although his team released a heartfelt message to the family on Thursday.

"The Denver Nuggets organization is devastated to learn about the tragic passing of Drew Gordon," the team said. "Drew was far too young to leave this world, but his legacy will forever live on through his three beautiful children and all of his loved ones."

"Our hearts are with Aaron and the Gordon family during this extremely difficult time."

Drew is survived by his wife and three children.

RIP