The 12-person jury is set to be back at work Wednesday as they decide whether Hernandez is guilty of murder in the June 2013 shooting death of Odin Lloyd.
Lloyd was killed in an industrial park less than a 1.6 kilometres from Hernandez's home. Lloyd was dating the sister of Hernandez's fiancee.
During closing arguments, Hernandez lawyer James Sultan acknowledged for the first time his client witnessed the killing. He described him as a 23-year-old kid who simply did not know what to do.
Sultan pinned the blame on two Hernandez friends.
The prosecutor said Hernandez planned the killing, shot Lloyd, then helped his friends flee.