Rogelio Armenteros

Armenteros didn't make his debut for the Astros last season, but his performance at Triple-A Fresno was strong enough for the team to add him to the 40-man roster in November for Rule 5 protection. After 21 starts and one relief appearance, he finished with a 3.74 ERA, striking out 26.7% of batters while walking 9.6%. All three of those numbers represented steps back from his 10-start cameo at the same level in 2017, when he recorded a 2.16 ERA on the strength of a 31.0% strikeout rate and 8.2% walk rate. Regardless, the results were strong enough to keep hopes of him being a future back-end starter alive. There's not a whole lot of optimism for him being more than that, as his fastball sits in the low 90s and only his changeup is a particularly interesting secondary pitch. On a deep Houston squad, it's hard to see him making a significant impact this season.