What is the date of the first game played by the American professional basketball team based in Massachusetts?
2017–18 NBA season:  The regular season will begin on October 17, 2017, earlier than previous seasons to reduce the number of "back-to-back" games teams are scheduled to play, with the 2017 runners-up Cleveland Cavaliers hosting a game against the Boston Celtics at Quicken Loans Arena in Cleveland, Ohio. Boston Celtics: The Boston Celtics are an American professional basketball team based in Boston, Massachusetts.
October 17, 2017