For years Coors Field has been seen as a hitter's dream and a pitcher's nightmare — a place where hitters' slugging percentages grow and pitchers' ERAs die. When it comes to fantasy baseball, the general rule of thumb has been to sit your starters when they're in Colorado.

But what about the Rockies' rotation? They make half their starts every season in the Mile-High City; how much value can they provide to fantasy owners?

Below I take a look at the 2018 outlooks, and breakdown the potential of each Rockies starting pitcher. Let's get to it.

Who's Starting in Denver?

Seven of the eight pitchers to start for the Rockies last year will be returning in 2018 after Tyler Chatwood signed a three-year deal to join the Cubs' rotation. Of the returning seven pitchers, four of them — German Marquez, Kyle Freeland, Antonio Senzatela and Jeff Hoffman — made their MLB debuts in 2017 and will be competing in Spring Training to remain in the rotation. Jon Gray — the sixth-place finisher in the 2016 NL Rookie of the Year voting — put up even better numbers in his second full season, while Tyler Anderson hit a sophomore slump. Meanwhile, veteran Chad Bettis returned from fighting testicular cancer to make nine starts at the end of the season

With an average age of 24.9, Rockies starters were the youngest in all of MLB in 2017 and they all have the potential to improve on their numbers in 2018, albeit some more than others. So which Rockies starters should be drafted this year and which should remain on the waiver wire?

Must Have in 2018

In his age 25 season, Gray was far and away the ace of the Rockies staff last year. He recorded a quality start in 10 of his 20 starts, and led Colorado starters with a 9.14 K/9 and a 3.67 ERA — the only starter with a sub-4.00 ERA. Gray also had the best ERA at Coors Field out of Rockies starters at 3.13, and he had the second-lowest WHIP at 1.217. Over three seasons, Gray has accumulated a career 9.5 K/9 and has lowered his ERA in back-to-back seasons now. Gray is the No. 43 starting pitcher in our preseason rankings — and is likely the only Rockies starter worth owning in mixed leagues this year — but he is in prime position to have a good year in 2018 and could end up at least a top-30 starting pitcher by season's end.

While not worth owning in mixed leagues, Marquez and Hoffman can both be valuable assets in NL-only leagues this season. Marquez was 19th among qualifying National League pitchers with a 8.17 K/9 last season, and was 14th with a 114 ERA+. He also recorded a quality start in 48 percent of his starts (14 of 29). And while Hoffman is currently projected on the Rockies depth chart as just outside the starting five, he could make a strong case this spring to crack the rotation. While still not great numbers, Hoffman's FIP was over a full run lower than his ERA last season, and he also had the third-highest quality start percentage on staff. Combine that with his 7.43 K/9 closely matching his career 8.1 K/9 in the minors, Hoffman has the potential for a breakout year in 2018.

Leave 'Em On The Wire

Anderson faltered in his second season in the majors, as his 4.81 ERA, 1.326 WHIP and 1.7 HR/9 innings were career-lows between the majors and the minors. On top of that, he recorded a quality start in only one-third of his starts and surrendered four or more runs in almost half of his starts. While he's not a lost cause by any means — an 8.48 K/9 last year and a career 7.4 K/9 in the minors is cause for fantasy owners to keep an eye on him — Anderson should not be drafted in 2018, even in NL-only leagues.

Along with Anderson, Freeland and Bettis should stay on all league's waiver wires — at least to start the year. Of the two, Freeland likely has the best potential of ending up on fantasy rosters at some point this season. His 46 percent quality start percentage was third highest on the team, and his 6.17 K/9 is right in line with his career 6.1 K/9 in the minors. But he recorded a 5.52 ERA over his final seven starts, and his 4.57 FIP for the season was higher than his ERA. These are a couple red flags that fantasy owners should stay away from Freeland until he can prove that he is pitching better.

As for Bettis, he has only had one year of fantasy relevancy in his career, and that came back in 2015 when he posted career-bests with a 4.23 ERA and 7.7 K/9. In the two years since then, he has posted a 4.84 ERA and 6.5 K/9 over 41 starts. So while he is definitely a player to root for as a fan for working his way back from fighting cancer, it is highly unlikely he will be worth owning on fantasy teams any time soon.

Looking Forward to 2019 and Beyond

On top of the young pitching that Colorado currently has in the majors, there are also several top prospects waiting in the minors for their shot at playing in Denver. Riley Pint, Peter Lambert and Yency Almonte represent the next wave of young starting pitching making their way to the majors, and all four of them bring high-strikeout potential.

At 23 years old, Almonte is the oldest of this trio and is the next in line to start for the Rockies. He has accumulated a career 3.95 ERA and 1.281 WHIP over six seasons, and has a 7.75 K/9 over the last three. Lambert posted career-bests with 1.9 BB/9 and 8.3 K/9 with the Lancaster JetHawks in 2017, while Pint has an 8.0 K/9 over two seasons in the minors. Pint needs to improve his control of the strike zone and cut down on his career 5.7 BB/9 rate, but he is considered the top pitching prospect in the Rockies system. At just 20 years old, he still has time to hone his skill and can become the future ace of the Rockies.

Long story short, there are a lot of good young pitchers coming up in Colorado right now. Some of them might not pan out for fantasy owners, but at the very least everyone should take a close look at the Rockies, because they might find some undervalued fantasy stars in the making.

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