Question: What is the date of the first game played by the American professional basketball team based in Massachusetts?
Related documents: [0]  [DOC] The Boston Celtics are an American professional basketball team based in Boston, Massachusetts. The Celtics compete in the National Basketball Association (NBA) as a member of the league's Eastern Conference Atlantic Division. Founded in 1946 and one of eight NBA teams (out of 23 total teams) to survive the league's first decade, the team is owned by Boston Basketball Partners LLC. The Celtics play their home games at the TD Garden, which they share with the National Hockey League (NHL)'s Boston Bruins. The franchise's 17 championships are the most of any NBA team, and account for 24.3 percent of all NBA championships since the league's founding in 1946. As a percentage of championships won, the Celtics are the most successful franchise to date in the major four traditional North American professional sports leagues. [END] 
[1]  [DOC] The 2017–18 NBA season will be the 72nd season of the National Basketball Association (NBA). 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. Christmas games will be played on December 25. The 2018 NBA All-Star Game will be played on February 18, 2018, at the Staples Center in Los Angeles, California. The regular season will end on April 11, 2018 and the playoffs will begin on April 14, 2018. [END] 
Answer: 
October 17, 2017
October 17, 2017