SIOUX FALLS, S.D. — The defense has rested in the trial of a South Dakota man accused of killing the 2-year-old son of Minnesota Vikings running back Adrian Peterson.

According to a press release, 29-year-old Joseph Patterson has pleaded not guilty to second-degree murder and other charges in the October 2013 death of Tyrese Robert Ruffin, who was the son of his girlfriend and Peterson.

Patterson maintains that Tyrese choked on a fruit snack. A doctor on Thursday testified for the defense, saying autopsy photos indicate injuries consistent with a child being given CPR after choking.

Investigators allege that Patterson assaulted Tyrese while they were alone in an apartment.

The trial resumes with rebuttal testimony Monday and closing arguments Tuesday. It’ll be the trial’s third week.

Patterson faces a mandatory life prison sentence if convicted of second-degree murder.