Ortiz was released by the Houston Astros on July 30. The veteran right-hander provides the Rockies with insurance after starting pitcher Aaron Cook was placed on the 15-day disabled list Saturday with a strained right shoulder.
Rockies manager Jim Tracy said right-hander Josh Fogg will take Cook's spot in the rotation Wednesday night against the Los Angeles Dodgers. Colorado trails the first-place Dodgers by 3½ games in the NL West but leads the wild-card race by three games over San Francisco.
Ortiz was assigned to Triple-A Colorado Springs and he pitched in relief Sunday for the Sky Sox, giving up one run and three hits in four innings. He walked two and struck out three against Reno.
Ortiz was 3-6 with a 5.57 ERA in 23 appearances, 13 starts, for Houston this year. After getting released, he signed a minor league deal with the New York Yankees and went 2-1 with a 1.59 ERA in three starts with Triple-A Scranton/Wilkes-Barre before getting released again.
He is 113-88 with a 4.48 ERA in 11 major league seasons with San Francisco (1998-2002, 2007), Atlanta (2003-04), Arizona (2005-06), Baltimore (2006) and Houston (2009). He reached double digits in victories for six consecutive seasons from 1999-2004, including four campaigns with at least 15 wins. The 2003 All-Star made his major league debut on April 2, 1998 with San Francisco.