Last with Oakland Athletics · P · No longer on a 40-man roster
Clayton Mortensen has an estimated 1 year and 104 days of major league service time — 1.104 in the notation clubs use, from 276 days credited on a major league roster.
| Season | Club | Days | Running total | How this season is known |
|---|---|---|---|---|
| 2009 | Oakland Athletics, St. Louis Cardinals | 36 | 0.036 | From transactions |
| 2010 | Oakland Athletics | 2 | 0.038 | From transactions |
| 2011 | Colorado Rockies | 69 | 0.107 | From transactions |
| 2012 | Boston Red Sox | 79 | 1.014 | From transactions |
| 2013 | Boston Red Sox | 90 | 1.104 | 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.