A female also was asleep in the passenger seat of Robinson's Chevy Impala when police officers approached the car at approximately 4:22 a.m. Both Robinson and the passenger had to be assisted out of the vehicle.
A police officer determined that Robinson wasn't impaired, so no DUI charges were filed against the 25-year-old running back.
Robinson's car was totaled. Authorities didn't observe any skid marks to indicate Robinson tried to hit his brakes before the car went into the water.
Robinson acknowledged the incident in a tweet Tuesday and said he "should not have been driving that late or when I was that tired."
The Jaguars said the team was "aware that running back Denard Robinson was involved in a single-car accident over the weekend and is thankful that nobody was injured."
Robinson has played for the Jaguars for three seasons, rushing for 914 yards with five touchdowns in 42 games (12 starts). He is expected to be used as a change-of-pace option in the backfield this season behind starter Chris Ivory.