MADISON, WI (AP) -

An Oregon man has pleaded not guilty to causing the massive brain injury that killed his girlfriend's 5-year-old son.

Twenty-four-year-old Dakota Black is charged with first-degree reckless homicide in the death of Brayden Turnbill. He died Oct. 24, two days after he was found injured at a home in Sun Prairie.

The State Journal reports a criminal complaint says Brayden's death was a homicide due to blunt force trauma to the head. Black and Shannon Turnbill were staying at the home of Turnbill's cousin at the time. The complaint says Turnbill came home from work and found her son having difficulty breathing.

A detective testified during Black's court appearance Thursday that Black denied injuring Brayden, but acknowledged he was the only adult home at the time Brayden collapsed.