A Miami-Dade jury on Thursday night convicted a sexual predator of fatally beating a convicted murderer while the two were housed in the same prison cell.

Jurors found Rickey Robinson, 49, guilty of second-degree murder in the slaying of Patrick “Sonny” Salgat, 57, in December 2010 in a dormitory at Florida City’s Dade Correctional Institution.

The slain man was serving life in prison for fatally shooting Santa Rosa State Attorney’s investigator Steve Bolyard in June 1990. Bolyard had been assigned to protect an ex-girlfriend of Salgat’s from his threats.

Salgat did not die until 45 days after his beaten body was found under a prison stairwell.

State records show that Robinson was serving an 18-year sentence for the 1990 sexual battery of a minor. Miami-Dade Circuit Judge Samantha Ruiz-Cohen will sentence Robinson on March 1.

Robinson was represented by Assistant Public Defender Kelly Foster. Prosecuting the case: Adam Goodman and Heloiza Correa.