Per The Athletic's Ken Rosenthal, Miller agreed to a one-year deal with the Rangers on Thursday after he appeared in nine games over the past two seasons combined.
Miller made four starts for the Arizona Diamondbacks in April 2017 before undergoing Tommy John surgery on his right elbow. The 28-year-old returned last June but landed on the disabled list with elbow inflammation for more than two months from July 12 through Sept. 28 after making four starts.
Rosenthal noted Miller is "healthy and ready to go" for the start of the 2019 season. Despite having one more year of team control next season, the Diamondbacks chose not to tender him a contract, allowing him to become a free agent.
Miller posted a 10.69 ERA over 16 innings in five appearances with Arizona in 2018. Since making at least 30 starts in three straight seasons from 2013 to 2015, the right-hander has started 28 games in 29 appearances since 2016.
With the Rangers needing rotation depth coming off a 67-95 record, Miller will join a low-pressure situation that allows him to audition for a long-term contract next offseason.