In February the club shut Chacin down early in Spring Training, and he felt better after two to three weeks and then ramped up for the season. The belief now is that a longer period of being forbidden from throwing should help the shoulder heal.
Chacin's recovery was set to begin Tuesday with a plasma-rich platelet therapy.
"Getting the PRP and strengthening and all that will help me to get better and get strong," Chacin said. "To not have the surgery was the best option.
"That surgery is really a tough surgery, so you just want to think about the future. I'm pretty happy with what we decided. With rest, I'm going to feel better. I did the rest and the strengthening in Spring Training, but it was only for two-three weeks, then it started feeling better. But after I started pitching, it overloaded and I started feeling better again."
The Rockies have six starting pitchers among nine players on the disabled list. Chacin, lefty Brett Anderson and right-handers Tyler Chatwood and Christian Bergman are all on the 60-day DL, although Anderson is close to returning. Right-handers Jordan Lyles and Eddie Butler are on the 15-day DL.
"It's been tough for the team," Chacin said. "A lot of pitchers got hurt. But a couple guys are coming back soon, so hopefully everybody is coming back soon and we can start playing better baseball."
Dugger said Chacin was not feeling pain but that the condition of the rotator cuff explained the drop in fastball velocity -- from 91-93 mph to 86-88 -- as well as why Chacin could reach the low 90s on a pitch and not approach it on the next several. While going 1-7 with a 5.40 ERA in 11 starts, Chacin had difficulty loosening up at the beginning of games, and his ability to work between starts also decreased as his time in the rotation progressed.
The good news for Chacin and the Rockies was that the fraying of the labrum was not pronounced enough to require surgery. Such a surgery could cost a player more than a season, and there would be time beyond that trying to regain form. Even then, the shoulder is often never the same.
"The cuff is beat up, bad," Dugger said. "But you have a better chance coming from rehab and basically changing your daily routine to maintain your arm strength.
"He's not in pain right now. So if you did a cuff surgery, the percentages are against you to come back as the type of pitcher you were. He might not be that guy that can throw 93-95. But you look at guys whose velocities drop but yet can keep that routine and that strength and that pace.
"Dr. Andrews was great about it. We filled him in about where we were in Spring Training, and we kind of knew what we were dealing with. He says, 'You didn't do anything wrong. You guys just logged some innings in, and now the cuff is a little revved up and it's a little weaker.'"
The year of injuries has turned a spotlight on Chacin's offseason throwing program, and it could be that pitching in Venezuela during winter ball may have been the missing ingredient. His two best Major League seasons -- 11-14, 3.62 ERA in 31 starts in 2011, his first full season, and 14-10, 3.47 last year -- came after winter league participation.
He didn't pitch in Venezuela last winter because he threw 197 1/3 innings for the Rockies last season, often enough for a club to advise against winter ball.
"The only two times I played in Venezuela, I get better for Spring Training," Chacin said. "[Not going] is not the same. You play catch, you're not pitching in a game. Maybe that's something I have to do -- not a lot of innings, but a couple, three, four, five starts. Some guys have to keep pitching and keep throwing to keep the arm loose."