The 2019 Boston Red Sox season was the 119th season in the team's history, and their 108th season at Fenway Park. The Red Sox entered the season as reigning World Series champions, but did not repeat, as they were eliminated from playoff contention on September 20. With a record of 84 wins and 78 losses, they finished third in the American League East, 19 games behind the New York Yankees. It was the first time the Red Sox did not win their division since 2015.

The 2018 Boston Red Sox season was the 118th season in the team's history, and their 107th season at Fenway Park. Under first year manager Alex Cora, the team finished with a 108–54 record, winning the American League East division title for the third consecutive season, and finished eight games ahead of the second-place New York Yankees. The Red Sox were the first MLB team to post 100 wins during the 2018 season, reaching that milestone for the first time since 1946; they were also the first team to clinch a berth in the 2018 postseason.