NFL's Shaq Thompson -- Blamed Cell Phone In Head-On Crash ... Cops Say

Carolina Panthers linebacker Shaq Thompson told police he was reaching for a dropped cell phone when he lost control of his car and smashed into another vehicle head-on early Sunday morning ... cops say.

Shaq -- the team's 2015 1st round draft pick -- was behind the wheel of a 2016 Chevy SUV which slammed into a 2004 Lexus SUV driven by former Duke QB Anthony Boone at 7:45 AM.

When cops arrived to the crash scene near Shaq's Charlotte-area home, the NFL player was given a breathalyzer -- which turned up traces of alcohol ... but cops say it was well BELOW the legal limit.

"He had some residual left over from the night before, but nothing where it was impairing or anything like that,” Sgt. Ben Miller of the State Highway’s Union County told the Charlotte Observer.

TMZ Sports also spoke with law enforcement officials who say Shaq said he had been playing music off his cell phone but dropped it ... and that's when he made the ill-fated decision to reach down and pick it up.

Officials tell us Boone was not wearing a seat belt -- and was hospitalized for a broken pelvis and broken ribs.

Shaq told police he was not seriously injured. He was not arrested -- but was cited for crossing the center lane.