'Doogie Howser, M.D.' Star Rif Hutton Dead at 73

Rif Hutton -- a familiar face to TV fans, especially to "Doogie Howser, M.D." devotees -- has died at 73 ... TMZ has learned.

His family tells us the veteran actor passed away at his home in Pasadena, California on Saturday after a battle with brain cancer, which he had been fighting for more than a year. We’re told he was surrounded by loved ones. He is survived by his wife and son.

Rif was best known for his role as Dr. Ron Welch on 'Doogie Howser' appearing in 17 episodes of the beloved medical dramedy that helped launch Neil Patrick Harris into stardom.

Beyond 'Doogie,' Hutton built a steady career across television, popping up in a string of recognizable shows over the years -- including "Star Trek: Generations," "JAG," "General Hospital" and "The Bold and the Beautiful."

Hutton stayed booked and busy ... carving out a decades-long career built on versatility. He took on everything from authority figures to conflicted professionals ... often popping up in one-off roles that left big impressions.

Hutton leaves behind a long list of credits and a legacy that spans decades of television. Online reports have his age as a decade younger, incorrectly.

Hutton was 73.