"I'm not nervous at all. I'm here to compete," Marquez said.
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Marquez, 22, is one of four starting pitching prospects who finished this past season in the Rockies' Top 30 Prospects list who will appear Sunday in split-squad games -- against the D-backs at Salt River Fields at Talking Stick, and against the White Sox at Camelback Ranch.
Marquez is fifth on MLBPipeline.com's 2016 Top 100 Prospects list and 73rd on the '17 list. Marquez will be followed against the White Sox by lefty Harrison Musgrave, who went 8-7 with a 4.30 ERA at Albuquerque this past season and was 25th on the Rockies' list at the end of '16.
Veteran lefty Chris Rusin will start against the D-backs, and will be followed by two righty prospects in Major League camp for the first time -- Yency Almonte, 19th on the Rockies' list, and Zach Jemiola, who wasn't on the Rockies' list but who earned 40-man roster designation after a solid year at Hartford and in the Arizona Fall League.
Marquez's easy fastball power and solid breaking pitch have drawn notice. But he realizes mastering the changeup could be his ticket to a successful starting career. The improvement area is making sure the arm speed is the same as his fastball, which runs 93-94 mph.
"It's got to be consistent," Marquez said. "I've been working all offseason on that thing, and Spring Training, too."
Almonte, 22, has been part of two trades -- from the Angels to the White Sox as the player to be named in the deal for infielder Gordon Beckham, and to the Rockies when the White Sox ended up with reliever Tommy Kahnle. This past year he demonstrated why he was so sought after by going a combined 11-10 with a 3.58 ERA at Class A Advanced Modesto and Hartford, with 156 strikeouts in 168 1/3 innings. He ranked third in the Class A California League in ERA, at 3.71.
Almonte comes with a fastball, slider and changeup from a low three-quarters motion. He is looking to control the slider's movement -- a project he took on in instructional ball -- and simply learn.
"It's a different vibe to me, to be here with the big guys like Chad Bettis, Tyler Chatwood, Jon Gray, all the guys I see on TV, and seeing the way they go about their business and picking their brains," Almonte said.
Jemiola, 22, went to Minor League camp this past year, expecting to repeat at Class A Advanced, but he was impressive enough in Spring Training to make Hartford's rotation. He went 8-10 with a 4.39 ERA and 92 strikeouts in 162 innings. Jemiola has a solid fastball-changeup combo, and he is making progress with breaking pitches.
"Everything came at me quick, and I was so thankful for it and so happy I was given the opportunity to do these things," Jemiola said. "My consistency with everything, I came into my own. I haven't completely figured it out, but I'm making progress."