"Revenge of the Nerds" star Robert Carradine was seriously injured in a head-on crash Colorado authorities say was caused by him making an illegal lane change.

Carradine, 60, was traveling on Highway 145 near Dolores when he allegedly crossed a driving line and directly collided into a semi-truck just after 2 p.m. on March 5. Carradine's wife, Edith, was also seriously injured in the crash, but like him is expected to survive. Their 2003 Mercury Marauder was totally destroyed.

"Why he drove out of his lane still has not been determined," Colorado State Police Sgt. James Saunders told the New York Daily News, adding "drugs and alcohol were not a factor."

Carradine has since been cited for careless driving, but investigators conceded the fact that he and his wife wearing their seat belts probably saved them from suffering even more serious injuries. Paramedics were quickly able to remove him from his vehicle and escort him to a local hospital with incapacitating injuries, TMZ reports. 

"In crashes with this magnitude of damage, seatbelts save lives," said Saunders. "It takes two seconds to put your seatbelt on. It's always worth it." The truck was not injured.

Carradine is best known for playing frat geek Lewis Slotnick in several "Revenge of the Nerds" films. He also plays the role of the dad, Sam McGuire, on the smash hit Disney Channel series "Lizzie McGuire."

Carradine has since been released from the hospital, but it remains unknown how long he was hospitalized. Carradine is the brother of the late David Carradine, who starred in the 1970s cult classic TV series "Kung Fu."

David Carradine was 73 years old at the time of his death. His Hollywood career spanned for more than four decades. He appeared in more than 100 movies; one of his last and most famous coming from his appearance in Quentin Tarantino's "Kill Bill."