In the top of the first inning, Astros right fielder George Springer broke his bat and a piece went flying over the netting on the home plate side of the visitors' dugout.
The fan who was hit was seated about five rows behind the field on the third-base side.
During the offseason, the Red Sox, along with other Major League clubs, extended the protective netting behind home plate at Fenway Park so that it stretches from one dugout to the other. The netting is nine-feet, eight-inches high from the top of the low field wall.
Aaron Leibowitz is a contributor to MLB.com based in Boston. This story was not subject to the approval of Major League Baseball or its clubs.