It also became only the second 8-3-5 triple play in MLB history, with the other having happened in 1884, when the Boston Beaneaters turned it against the Providence Grays.
The throw easily got Duvall. First baseman Matt Olson then alertly fired the ball across the diamond in plenty of time to get Masataka Yoshida at third after he tagged up and attempted to advance on Duvall's running gaffe.
Harris held up his arms and leaped as Austin Riley tagged out Yoshida, who was several steps away from the bag when Olson's throw arrived.
After Boston's victory, Duvall was able to chuckle about his own mistake.
"My instincts told me right off the bat that it was off the end," Duvall said. "I'm reading the outfielder. My goal is to get to second if it drops in front of him. I got out a little too far, and he made a good throw back. It's one of those things; it's risk/reward, and it didn't go my way tonight."
The play ended an inning that started with promise for Boston with back-to-back singles by Yoshida and Duvall.
The Associated Press contributed to this report.