SIOUX FALLS, S.D. (AP) — 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.

Twenty-nine-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.

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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.

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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.

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