SCOTTSDALE, Ariz. -- The uncertainty of the starting rotation was a source of angst during the Rockies' offseason, but it will be cause for intrigue once formal Spring Training workouts begin Friday at Salt River Fields at Talking Stick.Veteran lefty Jorge De La Rosa and righty Chad Bettis can be
SCOTTSDALE, Ariz. -- The uncertainty of the starting rotation was a source of angst during the Rockies' offseason, but it will be cause for intrigue once formal Spring Training workouts begin Friday at Salt River Fields at Talking Stick.
Veteran lefty Jorge De La Rosa and righty Chad Bettis can be inked into a five-man rotation that will begin the season April 4, provided they stay healthy. Hard-luck righty Jordan Lyles would go into the shoo-in category, as long as he isn't tripped by a freak injury such as the ones that have arisen the last two years.
Otherwise, the rotation is at the center of wild cards, questions and competition.
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The insiders: Logical rotation candidates are right-handers Tyler Chatwood and Jon Gray. Before undergoing Tommy John surgery in 2014, Chatwood had uncommon success at Coors Field (10-4, 3.92 ERA in 22 games, 18 starts). Chatwood, who also underwent the surgery as a teenager, is being treated as a starter going into camp. But the Rockies and Chatwood -- who finished 2014 by throwing about 50 innings in instructional ball in Scottsdale and in the Dominican Republic -- must monitor the condition of his elbow, and be ready to dial back if necessary.
Chatwood, 26, plans to take stress off the elbow by going to a cut fastball rather than a breaking ball. He'll try to gain feel for the pitch in Spring Training.
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Gray, 24, the Rockies' top pick in 2013, was called up in August for baby steps -- 40 2/3 innings over nine starts, to bring his total innings (Triple-A and Majors) for 2015 to 155. Now the Rockies plan to turn him loose, but Gray will have to display his electric fastball, and change speeds on both sides of the plate by effectively employing his changeup and his new curveball. Gray had his difficulties last spring (0-2, 5.93 in six games), and must earn a job or begin the year at Triple-A Albuquerque.
Don't forget us: Lefty Chris Rusin (6-10, 5.33 ERA) hurled two complete games, went seven innings twice, and had five starts of two or fewer runs, but the occasional blow-up led to the high ERA. Rusin is the most intriguing of the competitors. He is out of Minor League options, so a strong spring is essential.
Righty David Hale (5-5, 6.09 ERA) pitched through oblique and groin injuries, and reworked his delivery. Hale has a year of Minor League options, but hopes to crack the roster and stay. He was used in the bullpen last year, as well.
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Another chance: Two Rockies first-round picks -- lefty Tyler Matzek (11th overall, 2009) and righty Eddie Butler (46th overall in 2012) are coming off poor 2015 seasons and entering their final year of Minor League options.
Matzek, who shined at the end of 2014, unraveled last season in five starts (2-1, 4.09 ERA, 19 walks and three hit batters in 22 innings), and spent the rest of the year in the Minors. He hopes for a turnaround after undergoing therapy for performance anxiety.
Butler has struggled in multiple callups the last two years. Originally called up in 2014 at a time when he was already dealing with shoulder soreness, and had yet to develop a four-seam fastball as the Rockies requested, Butler showed little ability to make adjustments last season (3-10, 5.90 in 16 starts). Butler is still incorporating the four-seamer, but will base his style on his sinker, the way he did in college and the low Minors.
Pitchers and catchers report
First pitchers and catchers workout
Full squad reports
First full-squad workout
First Spring Training game
March 2 at Salt River Fields vs. D-backs, 1:10 p.m. MT.
Away vs. D-backs, April 4, 7:40 p.m. MT
Thomas Harding is a reporter for MLB.com. Follow him on Twitter @harding_at_mlb, listen to podcasts and** like his Facebook page**.