Jon Jones -- 'Model Inmate' ... During 1st Night in Jail

Jon Jones' first night behind bars in Albuquerque was a quiet one ... with officials telling TMZ Sports the UFC star was a "model inmate."

Jones turned himself in to authorities Tuesday morning after a warrant was issued for his arrest for violating his probation. As we previously reported, Jon was on probation from his 2015 hit and run conviction and officials believe his drag racing incident with cops last week may qualify as a violation.

We're told Jones is in a segregated cell at the Metropolitan Detention Center in Bernalillo County away from the general population because of his celebrity status. One official told us, "It's for his own protection."

A jail source tells TMZ Sports, "From the moment he walked into the jail, everyone knew he was there. It got around fast. Everyone knows who he is because he was just here a few months ago to speak as part of his community service."

As far as Jon's diet behind bars ... "he's on a standard 2,800 calorie plan."