Overall, Chacin finished his rookie season 9-11 with a 3.28 ERA in 21 starts and 28 games total. In the final nine starts, during the Rockies' final but ultimately unsuccessful playoff push, he was 4-2 with a 1.44 ERA. It was strong enough to suggest that he could be a breakout performer in 2011, even if a few key mistakes prevented the finish from being even better.
If the Rockies can avoid misfortunes such as injuries to key veterans, they will slot Chacin, who turns 23 on Friday, as the No. 4 pitcher in the rotation, behind ace Ubaldo Jimenez, left-hander Jorge De La Rosa and righty Aaron Cook. The Rockies see the positioning of Chacin as a way to protect him for now, but they see front-of-the-rotation talent.
In the Minors, Chacin, signed out of Venezuela, showed secondary pitches that were advanced beyond his years. He has been concentrating on improving his fastball at the Major League level. Even though he has not pitched a full year in the Majors, the Rockies believe he can put it all together sooner than later.
"There's no doubt that he possesses those qualities that can be at the forefront of the rotation," Rockies pitching coach Bob Apodaca said. "He has qualities of loving to compete, and the competition that he has against quality teams, because he does possess smoothness of stuff.
"It's not only breaking pitches, it's a fastball that darts with movement, and I think this was also a season he felt not only could he compete here, he could win here."
Interestingly, one of the most disappointing nights of 2010 helped increase the enthusiasm over Chacin.
On Sept. 24, Giants star Tim Lincecum retired the first 15 batters and held the Rockies to one run and two hits over eight innings. But Chacin gave up just three hits in seven innings. However, one sequence hurt. Chacin walked Buster Posey to open the seventh inning. Chacin worked ahead of veteran Pat Burrell, 0-1, then left a slider over the plate. Burrell's two-run homer gave the Giants a 2-1 victory.
"That was a big game that we lost, but he pitched his rear end off," Rockies general manager Dan O'Dowd said. "He's a competitive kid. He has no fear."
To prepare for this season, Chacin has to match smarts with his fearlessness.
He faces a different challenge from many of the Rockies' pitchers because of his frame. Chacin is listed at 6-foot-3 and 215 pounds, but his husky body type allows him to carry more muscle weight. The problem is, his mechanics work better when he's in the 205-215 range.
Chacin said last season he received diet tips from Jimenez, who grew up on the hearty Latin American meals of chicken, rice and beans in the Dominican Republic but learned to mix vegetables into his repertoire after going pro. Chacin also has emulated Jimenez's distance-running routine between starts. Chacin has spent much of the offseason training in Tucson, Ariz., with the Rockies seeing progress. He plans to come to Denver later this month, then go to the Dominican Republic to work with Jimenez and other Latin American pitchers before Spring Training.
"I'm going to work more on my body, get a little more in shape for next year. I'll do what I have to do and be ready for next year," said Chacin, who began 2010 at Triple-A Colorado Springs and spent time there in July and August, but nonetheless set club rookie records for ERA and strikeouts (138). "I want to lose some more weight. I lost like five or seven pounds and I want to be more in shape. I went through the year all healthy, no pain. I want to pitch a lot of innings, try to win the most games I can and try to help the team win."
Even in the Minors, the Rockies had to modify his training program to keep his body as that of a pitcher, rather than a linebacker.
"He's a mature-bodied kid, unlike Ubaldo or Esmil Rogers or Sammy Deduno, who have lankier frames," Rockies player development director Marc Gustafson said. "If he came in and did squats, he could probably lift a lot of weight. For him, we have to do a lot of footwork and agility work, even if it's jump rope -- the old-school way."
O'Dowd said, "His command of his fastball has got to get better, and that's tied to his weight and keeping his body under control and not trying to do too much with it. This guy's got good stuff."
As last year evolved, Apodaca said he saw Chacin developing the intangibles of a big winner.
"He has that inner control that he doesn't beat himself to death, that he learned from that experience," Apodaca said. "[Chacin says,] 'I've got to learn what guys to throw certain pitches to, and when I need to make an important pitch I'm totally prepared. I know how I can attack him.' He's years ahead of his time as far as maturation and controlling his body language. He's very bright and a bright spot for our ballclub."
Thomas Harding is a reporter for MLB.com. Read his blog, Hardball in the Rockies, and follow him on Twitter @harding_at_mlb. This story was not subject to the approval of Major League Baseball or its clubs.