Hartlieb signed a minor-league contract with the Rockies on Monday.
Hartlieb spent the large majority of the 2023 campaign with the Triple-A affiliate of the Marlins in Jacksonville, where he posted a 3.63 ERA and 46:18 K:BB across 44.2 innings. The 29-year-old righty has logged only nine relief appearances at the major-league level since the beginning of the 2021 season, but he could factor into Colorado's bullpen mix in 2024.