Washington State president Kirk Schulz tweeted, "Our thoughts and prayers are with the Hilinski family".
WSU coach Mike Leach: 'He was an incredible young man and everyone who had the privilege of knowing him was better for it'. Thoughts and prayers are with the Hilinski family.
A vigil for the late WSU quarterback Tyler Hilinski was announced for 7 p.m. Friday at the Cougar Statue on campus.More news: Trump Is Now Claiming He Wants Immigrants To Come In From "Everywhere"
Hilinski, a redshirt sophomore, took over for Luke Falk in the Holiday Bowl after the starting senior quarterback injured his wrist. The coroner confirmed the manner of death as suicide.
He played in eight games in the 2017 season, highlighted by the September 9 game where he led the Cougars to a triple-overtime win against Boise State.
Washington State athletic director John Johnson called Hilinski "a tremendous individual, great friend and teammate".
On Thurday, the Whitman County Coroner's office officially ruled on Hilinski's death.More news: U.S. withholds $65 million from United Nations aid for Palestine
Hilinski was the presumptive starting quarterback going into next season.
"The tragic news today surrounding Tyler Hilinski is devastating to all". He was expected to lead Washington State onto the field next season as well. He had not shown up for football practice earlier in the day.
Out of his seven games played in the crimson and grey, Hilinski's triple-overtime victory over eventual Mountain West champion Boise State stands out as a career highlight.
Hilinski enrolled at WSU in January 2015 after attending Upland High School in Southern California. "The university will continue to coordinate and provide ongoing counseling care for all student-athletes as along as needed".More news: Australian Open: Federer rolls, Sharapova and Djokovic get comeback wins