He returned from the hospital with bad news just before the Rockies took the field for the nightcap: He is lost for the season with a torn ligament in his left elbow.
An MRI revealed De La Rosa, the Rockies' best pitcher this season, has a complete tear of the ulnar collateral ligament. He'll need Tommy John-style tendon replacement surgery, a procedure that will sideline the hard-throwing left-hander for a year.
De La Rosa left the game with one out, two runners on and a 1-and-1 count on Chris Young in the third.
"As the at-bat progressed it became more evident that there was something wrong. I thought maybe it was a blister or nail issue," catcher Chris Iannetta said. "I went out and talked to him and he didn't really sound good. I saw his demeanor while he was receiving signs and said enough's enough."
De La Rosa assumed he just had tightness in his elbow, and manager Jim Tracy let him take a practice pitch but pulled him as soon as he saw him grimace.
"He said let me keep pitching. OK, let's throw a pitch and see what it looks like,' " Tracy recounted. "Well, I was watching very closely when he threw it and all I had to see was the expression on his face when he turned the ball loose and I said, 'That's all.' "
De La Rosa was the Rockies' top pitcher with a 5-2 record and a 3.51 ERA. He was coming off his first career complete game when he got hurt.
Iannetta said he "gave him (De La Rosa) a hug and said I'm sorry," when he heard the news.
"There wasn't much time to talk. He loves baseball and he loves this team," Iannetta said. "He's obviously extremely upset about it. It's a tough loss but everyone's gotta step up."
With Ubaldo Jimenez still searching for his first win, De La Rosa had been the Rockies' rock.
"He was a big part of our team," said Greg Reynolds, who won the opener in relief. "There's not too many guys that have stuff like Jorge. Someone's going to have to step up. If that's me, I'll be ready for the challenge. If I'm picked to fill the role, I'll give it everything I got and I'll be ready for it."
Aaron Cook (fractured finger) is set to come off the 60-day DL May 30, although if he makes his final rehab start Saturday he won't be ready to return until the first week of June.
The Rockies are a resilient bunch, Tracy said, pointing to their surge last season when closer Huston Street started off on the DL, All-Star shortstop Troy Tulowitzki missed 40 games with a broken wrist and even De La Rosa missed two months with a finger injury.
"Obviously, it's a hit," Tracy said. "I can tell you this right now. We have to move on and find ways. We've done it before."
"It's devastating," Jason Giambi said. "He was having a phenomenal year for us, too. I feel terrible for the kid. He was really putting it together. That happens in baseball and now we've got to pull together."
Information from The Associated Press was used in this report.