DeKALB — The NIU sports world was shaken Thursday when it was announced former football player Alex Kube passed away at 29.

Kube died at 11:50 p.m. Wednesday at Rockford Memorial Hospital. A Thursday autopsy to determine the cause of death is pending results, according to the Winnebago County Coroner’s Office.

Kube, who played for NIU from 2007-10, erupted onto the scene during his 2007 freshman season.

He led the team with 111 tackles — which was the first time in 31 years that a freshman led in tackles — and was tied for second in tackles in the NCAA for a first-year player.

Kube had aspirations to join the NFL after graduating NIU with a communication degree and had tryouts with the Chicago Bears and Minnesota Vikings lined up. However, Kube started a business called Elite 7 Performance, where he trained aspiring athletes.

One of those young, aspiring athletes was friend and trainee of Kube’s at Elite 7 Performance, Daniel Faccone, 16, a sophomore at Prairie Ridge High School in Crystal Lake.

“It’s unreal [because] he meant so much to me, and I never got to tell him that,” Faccone said. “Knowing him, I know he would want me to keep pushing forward. I’m going to dedicate my life to him.”

Faccone said Kube was very unselfish and mentioned how Kube always made sacrifices for people without expecting anything in return.

“Seeing the best out of us made him happy,” Faccone said. “I hope to be half the man he was, [and] it was an absolute privilege to know him.”

Another person affected by the passing of Kube was former friend and trainee partner, Sean Folliard, who was a linebacker for the Huskies from 2013-16.

“He had such a huge personality, big heart and cared so much about everyone,” Folliard said. “Kube was family, and I can’t put it into words how much he really meant to me.”

Folliard said Kube will be known for being a ‘ferocious competitor’ on the field and someone who changed lives and led people into their dreams off the field.

“Thoughts and prayers are with the Kube family,” said football Head Coach Rod Carey in a statement Thursday via Twitter. “We have heavy hearts today. He will be missed as a husband, son, friend and teammate.”

Cary-Grove High School, Kube’s alma mater, 2208 Three Oaks Road, Cary, 60013, declined to comment.