DENVER -- Rockies right-handed relief prospect Carlos Estevez admitted that pitching against players older than him was an adjustment.
With a fastball capable of triple digits, the strapping Estevez -- who, according to scouts, has outgrown his 6-foot-4, 210-pound roster listing -- cruised through Class A Advanced Modesto last season (5-0, 1.37 ERA, five saves in 14 appearances).
Estevez's first 23 appearances for Double-A New Britain resulted in a 5.26 ERA. But once he settled in against the more savvy hitters, Estevez was scored upon just once in his final 11 games. A solid performance in the Arizona Fall League (1-2, 3.97 ERA with six saves in 11 appearances) helped Estevez, 23, land a spot on the Rockies' 40-man Major League roster and rank No. 30 on MLB.com's Rockies prospects list.
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"There's a big difference," Estevez said in Spanish during a video interview at the MLB Rookie Career Development program in Washington. "People say, 'Well, the next league is the next step.' But when you get to Double-A, you start to find guys who aren't your age. There are more veteran guys, for example. I was about average age in Class A [Advanced]. But then I found myself in Double-A with players who were 30, 31 or 28. I was the youngest among the relievers in Double-A."
Estevez, who signed out of Santo Domingo, Dominican Republic, and joined the organization in the Dominican Summer League in 2011, seemed ready for a higher competition level in the Fall League.

"In the Arizona Fall League, I found a lot of players who had also been in the big leagues," Estevez said. "From that, I can learn how to pitch in the big leagues. That gives me a live example of what the big leagues are.
"With that I can prepare, because pitching is a mental game, learning how to pitch to hitters. So in that way, I'm learning how to pitch in the big leagues."
Estevez will get to face big leaguers in Spring Training to see how far he is from facing them for real. His secondary pitches are still developing, but he has the power that the Rockies have been trying to add to the Major League bullpen. Over the past year, general manager Jeff Bridich has traded for Jairo Diaz (from the Angels) and Miguel Castro (Blue Jays). The homegrown Estevez fits the program of collecting hard throwers.
"That's a big power arm -- he's probably more like 6-6, but it's a big horse of a man," Rockies senior director of player development Zach Wilson said. "His fastball sits at 97-98 [mph]. He can take it all the way up to 100, with a slider and changeup. He's a power right-hander who's got a chance to pitch in the back of the bullpen."