Arroyo, 37, has been one of baseball's most durable pitchers over the years, making at least 32 starts and throwing at least 199 innings every season from 2005-13. A back injury sent him to the disabled list for the first time earlier this year, before the elbow starting acting up.
In 14 starts and 86 innings this season, Arroyo went 7-4 with a 4.08 ERA. He is in the first year of a two-year, $23.5 million contract. Given the timing of the injury, Arroyo won't return to the D-Backs until the second half of the 2015 season, assuming no setbacks.
Arizona comes into Monday with the second worst record in baseball at 37-53. They have already started selling off veterans, trading Brandon McCarthy to the Yankees and both Joe Thatcher and Tony Campana to the Angels over the weekend.