I don't know what ERod's injury might be, but....
...his velo has been down a little, his Change hasn't been as effective, he's getting a lot fewer swings/misses, and a lot less LOB, but he's actually doing OK overall.
Unless there's some injury, the so-so results so far could just be early-season blahs, especially with no spring training.
Let's hope there's no injury. When healthy, he was one of the top 20-25 starting pitchers in the MLB in 2019-2021.
Side-note, his BABIP on grounders was high in 2019 and 2021, despite the overall success, probably because every IF position on BOS was in the bottom 10 in both 2019 and 2021. That more than anything seemed to contribute to his ERA being significantly higher than his FIP and xFIP.