Ronald Phillips was pronounced dead at the Southern Ohio Correctional Facility in Lucasville at 10:43 a.m. EDT (1443 GMT), the Ohio Department of Rehabilitation and Correction said in a statement.
The execution and had been delayed multiple times as a court fight plays out over the state’s use of a drug mixture for lethal injections. The U.S. Supreme Court had denied appeals from Phillips late on Tuesday.
Phillips in January 1993 was dating Fae Evans, the mother of three-year-old Sheila Marie Evans, when she left her daughter with Phillips in her apartment, according to court documents.
Fae Evans returned home to find the child motionless and cold. Sheila Marie Evans was brought to the hospital and underwent emergency surgery but died.
Doctors performed an autopsy and found extensive bruising as well as internal trauma, according to court documents.
Phillips confessed that he had become enraged when the girl would not respond to him calling her for breakfast, court documents showed.
He beat and then sexually assaulted the toddler. Phillips also admitted to previously raping the girl twice, according to court documents.