SIOUX FALLS, S.D. (AP) — A man accused of killing the 2-year-old son of Minnesota Vikings running back Adrian Peterson two years ago is set to stand trial in South Dakota.

Opening statements in the case of 29-year-old Joseph Patterson are scheduled to begin Monday.

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.

Investigators allege that Patterson assaulted Tyrese while they were alone in a Sioux Falls apartment. The boy died at a hospital and doctors determined that the blows to his head couldn't have been accidental.

Patterson has denied hurting Tyrese and said he choked on a fruit snack.

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

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