The Diamondbacks traded away Daulton Varsho, who hit 27 home runs and 74 RBIs last season (592 PAs), who ZiPS projected to hit 25 home runs and 73 RBIs this season (534 PAs).
The impact of the loss of Varsho will be about 9 home runs. Varsho’s 534 PAs projected by ZiPS will likely go to Pavin Smith and Corbin Carroll. Together they will hit about 13.5 home runs (based on HR/PA projected by ZiPS), and if catcher Gabriel Morena takes Herrera’s PAs, that will be an extra 2.7 home runs. The difference is about 9 home runs.