Last with Tampa Bay Rays · P · No longer on a 40-man roster
Diego Castillo has an estimated 4 years and 167 days of major league service time — 4.167 in the notation clubs use, from 855 days credited on a major league roster.
| Season | Club | Days | Running total | How this season is known |
|---|---|---|---|---|
| 2018 | Tampa Bay Rays | 119 | 0.119 | From transactions |
| 2019 | Tampa Bay Rays | 172 | 1.119 | From transactions |
| 2020 | Tampa Bay Rays | 172 | 2.119 | From transactions |
| 2021 | Seattle Mariners, Tampa Bay Rays | 172 | 3.119 | From transactions |
| 2022 | Seattle Mariners | 172 | 4.119 | From transactions |
| 2023 | Seattle Mariners | 30 | 4.149 | From transactions |
| 2024 | Minnesota Twins | 18 | 4.167 | From transactions |
172 days credit a full year, so a season adds at most 1.000 no matter how long a player is on a roster. 3.000 years reaches salary arbitration and 6.000 reaches free agency —
what every threshold unlocks.
This figure is an estimate reconstructed from public roster
transaction records. It is not an official MLB or MLBPA figure — those are
not published. See the
methodology.
Last updated 2026-10-12.
Independent project, not affiliated with or endorsed by Major League
Baseball or the MLBPA.