Esteban Loaiza -- accused of possessing over 40 lbs. of coke -- was sprung from county jail in San Diego ... but he ain't goin' home, 'cause the ex-MLB star was moved to a federal jail.
Loaiza -- a 2x MLB All-Star who played 14 seasons in the big leagues -- has been behind bars at San Diego County Jail since being arrested February 9 on multiple felony drug charges.
After consulting with federal prosecutors, the San Diego D.A.'s office tells us they decided to drop all charges against the former White Sox pitcher, so he could instead be charged federally.
Yesterday, U.S. prosecutors charged Loaiza with possession of cocaine with intent to distribute ... and he was transported to Metropolitan Correctional Center in San Diego -- a federal facility primarily used to hold inmates awaiting trial.
MCC currently holds about 900 inmates -- male and female -- of all security levels.
Loaiza -- who is facing 10 years to life in prison, if convicted -- is due back in court March 12.