The 2017 Arizona Diamondbacks season was the franchise's 19th season in Major League Baseball and their 19th season at Chase Field and in Phoenix, Arizona. They began the season on April 2 at home against the San Francisco Giants. The Diamondbacks finished the season 93–69 to finish in second place in the National League West Division, 11 games behind the Los Angeles Dodgers. They also flipped their record from the previous year, in which they went 69-93.
On September 24, the Diamondbacks clinched a Wild Card berth with losses by the Milwaukee Brewers and the St. Louis Cardinals. They also clinched home field for the Wild Card game after a 3–2 walk-off victory over the Miami Marlins. This marked the first trip to the playoffs for the Diamondbacks since 2011. In the Wild Card Game, they defeated the Colorado Rockies to advance the National League Division Series against the division rival Los Angeles Dodgers. The Diamondbacks were then swept by the Dodgers in three games, ending their postseason run.
Offseason and spring training
During their pre-season spring training, the Diamondbacks participated in the Cactus League, finishing with a 15–15 win–loss record. They also played two tied games that were not included in the standings.
Regular season
Facing the Los Angeles Dodgers on September 4, Diamondbacks outfielder J. D. Martinez became the 18th player in MLB history to hit four home runs in a game. This performance meant that the Diamondbacks became the first team ever to have had a 20-strikeout game in nine innings (Randy Johnson, 2001), a perfect game (Johnson again, 2004) and a four-homer game (Martinez).