Jeff Sperbeck, the longtime agent and close friend of NFL legend John Elway, died in what California investigators are calling an accident.

The Riverside Sheriff’s Coroner has determined that the reason for the death was a severe injury to the head. This happened when Sperbeck fell while a golf cart was in motion on April 26 in La Quinta, California.

The incident occurred at the Madison Club, where Elway was reportedly driving the cart.

“The cause of death is “blunt head trauma,” and the manner of death is “accident” and the mode of death (how the injury occurred) is “passenger fell from golf cart,” the office said in a statement Friday.

Authorities found no evidence of criminal activity or mechanical failure in the death of the 62-year-old.

Shortly after the accident, Elway’s attorney, Harvey Steinberg, told 9NEWS in Denver: “This has been a terrible time for everyone involved, and our hearts continue to go out to the Sperbeck family. As John grieves this unimaginable loss, we appreciate the efforts of the Riverside County Sheriff’s Department.

“The investigation has confirmed what we already knew: This was a tragic accident and sometimes things happen in life that we will never comprehend.”

Elway expressed profound sorrow over the loss, saying, “I am absolutely devastated and heartbroken by the passing of my close friend, business partner and agent Jeff Sperbeck,” Elway previously said in his own statement.

“There are no words to truly express the profound sadness I feel with the sudden loss of someone who has meant so much to me,” Elway continued. “My heart and deepest sympathies go out to Jeff’s wife, Cori; his children Carly, Sam and Jackson; and everyone who knew and loved him. Jeff will be deeply missed for the loyalty, wisdom, friendship and love he brought into my life and the lives of so many others.”

Sperbeck had a distinguished career as an NFL agent, representing over 100 players and co-founding the wine brand 7Cellars with the Hall of Famer Elway.