The Seattle Mariners have emerged as a model for building a successful starting rotation, boasting a group that had remarkable performances last season. Four of their five starters were developed through their own system, contributing to a rotation with impressive statistics, including all five maintaining a sub-3.50 ERA.

However, the latest projections from FanGraphs suggest potential challenges ahead. Despite being ranked as having the second-best rotation in baseball, the Mariners face concerns about injuries and performance drops among key pitchers, which could lead to a frustrating 2025 season.