Kauffmann was optioned to Triple-A Albuquerque on Sunday.
The 25-year-old gave up a run over three frames in Saturday's blowout loss to the Angels and was the only Rockies pitcher to surrender fewer than six runs, but he'll still lose his spot on the active roster. Kauffmann has been ineffective in his first taste of the big leagues this year with a 10.19 ERA, 2.04 WHIP and 8:10 K:BB across 17.2 innings.