Scott finished 72 holes at 11-under 273, then waited in the clubhouse as Justin Rose (68), five-time 2013 winner Tiger Woods (69) and Gary Woodland (73) each failed to convert a birdie on the 18th hole.
The three -- plus Graham DeLaet (65) -- finished one shot off the pace at 10-under 274, handing the Barclays crown to the Australian, whose only other win this year came at The Masters.
Ricky Fowler (70), defending champion Nick Watney (69), Matt Every (68) and Jason Kokrak (67) tied for ninth one shot further back.
NBC reportedly holds celebs hostage to Jimmy Fallon's show
Aaron Carter is still in love with Hilary Duff