For a quick explanation of the Rule 5 draft, along with which Diamondbacks prospects were protected, click here. For an even more detailed explanation of the Rule 5 draft, click here.
The Diamondbacks have made selections in each of the past three Rule 5 drafts: in 2016 they selected reliever Tyler Jones, but returned him to the Yankees before the season started. In 2017 they took another reliever/emergency starter in Albert Suarez but he also failed to make the roster and was eventually released. In 2018 they chose starting rhp Nick Green (to the confusion of many snakepitters) and, like Jones, was sent back to the Yankees without making a big league appearance.