De La Rosa, who has pitched in a "B" game this spring, threw 45 pitches and gave up two runs on three hits in the outing. He expects to receive the results from the MRI on his groin Monday.
"I might miss the next two starts, I don't know," De La Rosa said. "It's really sore right now. I know I'm not going to throw for a few days because I can feel the pain."
It's unclear if De La Rosa's injury will keep him from starting the April 10 home opener against the Cubs. He is receiving treatment and expects to know more next week.
"We still have a little time before he's throwing [side sessions]," Rockies manager Walt Weiss said. "We are assessing him every day. It could be worse with him."
Jesse Sanchez is a national reporter for MLB.com. Follow him on Twitter @JesseSanchezMLB. This story was not subject to the approval of Major League Baseball or its clubs.