A motorist was seriously injured in a two-vehicle crash early Sunday on the Garden State Parkway. Two vehicles were traveling north near milepost 137.9 in Cranford Township around 4:45 a.m. when an Acura struck the rear of a Mazda, according to a New Jersey State Police spokeswoman. The Mazda ran off the roadway and struck a tree, while the Acura caught fire after the collision, police said. The Mazda driver, a 27-year-old Allentown, Pennsylvania, resident, suffered serious injuries and was taken to a hospital for treatment. The Acura driver was uninjured. The crash remains under investigation…