2021 Colorado Rockies Diamonds in the Rough

by Matt Wiener
2021 Colorado Rockies Diamonds in the Rough

Welcome to the ninth installment of my series 2021 Diamonds in the Rough. In this article, I will breakdown two hitting and two pitching prospects from the Colorado Rockies farm system.

Last time out, I took a look at some of the Cleveland Indians prospects.

In deep dynasty leagues, the ability to spot high-upside lower-ranked prospects before they become household names in the fantasy baseball community can make a big difference to the long-term success of your team.

To qualify as a diamond in the rough for this series, a player must be currently ranked lower than No. 15 on their team's latest MLB Pipeline Prospect Rankings.

Check out our 2021 Fantasy Baseball Dynasty Rankings to help you dominate your leagues.

2021 Colorado Rockies Diamonds in the Rough


Eddy Diaz, 2B/SS (#22)

Bats: R | Throws: R
Tools: 50 Hit | 35 Power | 65 Run | 55 Field | 50 Arm
Age: 21
Highest Level: Rookie 
ETA: 2023

The Rockies signed Eddy Diaz, the first Cuban player ever signed by the Rockies, for $750,000 during the 2017 international free agent signing period.

The first thing you need to know about Eddy Diaz is that he is one of the premier base stealers in all of baseball. Not just the minors. All of baseball.

In 126 career games across the Dominican Summer League and Pioneer League, Diaz has racked up an unbelievable 104 steals. For those counting at home, that is a pace of almost 134 steals over a 162 game season. Not only does Diaz swipe an absurd amount of bags, he does so with great efficiency. In 127 attempts, Diaz was only caught stealing 23 times. Though partially attributable to the low-level competition and obviously unsustainable, Diaz has plus speed and his gaudy steal numbers are worthy of our attention.

Diaz compliments his elite base running ability with an above-average hit tool and a knack for getting on base. Over 555 professional plate appearances, Diaz sports an excellent .317 BA and .397 OBP.

The biggest knock on Diaz is his lack of power. In his professional career, Diaz has yet to hit a home run. However, that does not mean that Diaz does not hit the ball hard. In fact, Diaz has compiled a solid .434 SLG and above-average .831 OPS. Though not having a home run, nearly 29% of Diaz's hits have gone for extra-bases (including 12 triples).

Despite his aggressive approach at the plate, Diaz has demonstrated solid plate discipline early in his career. Over 378 plate appearances between 2017 and 2018, Diaz walked (50) more times than he struck out (38). However, over 177 plate appearances in 2019, Diaz saw his strikeout rate (K%) jump 11% and his walk rate (BB%) plummet almost 10%. Yet, in 2019, Diaz still possessed a better than average 18.8% K%.

Diaz has lightning-quick bat speed and is a proven fastball hitter. It is because of this bat speed and some remaining projection in his 6-foot, 175-pound frame that I think Diaz has the potential to approach double-digit power.

Other than power, Diaz possesses all of the traits that get me excited about a young prospect. Diaz is an elite baserunner who has displayed good plate discipline and the ability to get on base and hit for extra-bases at a high clip. Further, Diaz possesses good defensive versatility, which should help him rise up the ranks.

Like Jhonkensy Noel, who I covered in my Cleveland article, Diaz is one of those guys that I have in almost every deep dynasty league. With his combination of elite speed and on-base ability,  I firmly believe that Diaz is on the verge of elevating his prospect status and becoming a household name.

Connor Joe, OF (Unranked)

Bats: R | Throws: R
Tools: 55 Hit | 45 Power | 45 Run | 50 Field | 45 Arm
Age: 28
Highest Level: MLB
ETA: 2021

The Pittsburgh Pirates drafted Connor Joe out of the University of San Diego (San Diego, CA), in the 1st round (39 overall) of the 2014 MLB draft.

In the words of the great Sir Paul McCartney, Joe's professional career has been a long and winding road. Though Joe is already 28 years old and has only played eight games in the MLB, he has already been on four different teams (not including two stints with the Dodgers). In fact, Joe served as the opening day starting left fielder and number six-hitter for the 2019 San Francisco Giants.

After three mostly pedestrian seasons in the minors, Joe broke out in 2018. Across AA and AAA, Joe hit .299/.408/.527 with 17 HR, 55 RBI and 69 runs over 435 plate appearances. Prior to 2018, Joe had only managed 11 HR over 1,155 plate appearances. Further, Joe posted an excellent 60/88 walk-to-strikeout ratio (BB/K).

After a breakout 2018, Joe showed that he was for real, improving his numbers across the board in 2019. In 2019, Joe dominated AAA pitchers with a superb .300/.426/.503 slash line. In addition, Joe compiled 15 HR, 68 RBI and 82 runs over 446 plate appearances. Joe's trademark plate discipline was on full display, as he posted an even better 72/81 BB/K. Moreover, Joe posted an above-average 18.2% K% and an excellent 16.1% BB%. For reference, according to Fangraphs Sabermetrics Library, a BB% of 15% is considered "Excellent," the highest possible rating.

There were high expectations for Joe coming into 2020. But before the 2020 baseball season was canceled, tragedy struck. On March 18, 2020, Joe announced that he underwent surgery for testicular cancer the day prior.

According to Joe,  "I was really focusing on getting healthy and being there for my family. Baseball never crossed my mind, whether I'd not be able to play. I was focused on going through the treatments, attacking those day-by-day, just making it to the next day."

After being declared healthy (five months to the day of his diagnosis) and ready to play in the offseason, the Rockies signed Joe on November 15, 2020, to a minor league contract with an invite to spring training. So far in 2021 Spring Training, the Joe signing has looked like a shrewd move for the Rockies. Over 27 plate appearances, Joe has hit an absurd .400/.556/.950 with three HR, seven RBI, and eight runs.

Joe is an on-base machine. In the words of Rockies' assistant general manager Jon Weil, "[Joe has] a good approach at the plate. He's not afraid to talk a walk, get on base and do the little things that hitters need to do." Over 495 minor league games, Joe compiled a .797 OPS and a .377 OBP. Further, Joe's power made significant strides in 2018 and 2019.

Needless to say, Joe is an amazing story. Joe has a professional approach at the plate and a good command of the strike zone. If the Joe Show continues, it is going to become increasingly hard for the Rockies to keep Joe off the big league roster.

Guys like Joe are perfect end of the bench roster pieces in deep dynasty OBP leagues. The talent and pedigree are there and if Joe works his way into regular playing time, all of a sudden you have a 28-year-old regular with potential in a deep dynasty league for free. Don't overthink it.


Gavin Hollowell, RHP  (#29)

Bats: R | Throws: R
Tools: 55 FB | 55 SL | 50 CNTRL
Age: 23
Highest Level: Rookie 
ETA: 2022

The Rockies drafted Gavin Hollowell out of St. John's University in the 6th round (189 overall) of the 2019 MLB draft.

Hollowell is a rare case in this segment. Oftentimes, I will break down a pitcher and explain the traits that mitigate his bullpen risk. However, in the case of Hollowell, he has a pure bullpen profile. Maybe I am biased because Hollowell attended my law school alma mater, but I see elite reliever upside with Hollowell.

Hollowell dominated as a freshman (1.65 ERA) and sophomore (2.16 ERA) out of the bullpen at St. John's. Though Hollowell's ERA rose to 4.23 during his junior season in 2019, he also posted a career-high 11.3 K/9. In addition, Hollowell compiled nine saves (eighth on the program's single-season record list), six of which required four or more outs. Moreover, Hollowell ended the season on a tear. In his final 12 appearances (26.1 innings), Hollowell went 1-0 with a 2.05 ERA and eight saves, striking out 36 and walking just six over that span.

During his time at St. Johns, Hollowell held opponents to a weak .207 BA against and compiled 17 saves (the fourth-most in program history).

After the Rockies drafted Hollowell high for a reliever, he enjoyed a dominant 2019 debut in the Pioneer League. Over 17 appearances (18.2 innings), Hollowell compiled a perfect 3-0 record, with a 2.89 ERA and 1.02 WHIP, striking out 30 and walking just five over that span. Further, Hollowell blew past his career-high K/9 (14.5 K/9) and posted an off-the-charts 39% strikeout rate (K%) and a microscopic 6.5% walk rate (BB%).

Standing at 6-foot-7 and 215 pounds, Hollowell has a towering frame with the remaining projection. Hollowell's arsenal features a fastball with good vertical movement that currently sits 94-95 mph and hits 96 mph, with the potential to add a few ticks as Hollowell grows into his frame. In addition, Hollowell possesses a plus tilting slider that sits at 83-84 mph with good spin. Both of Hollowell's offerings play well off each other and generate tons of swings and misses.

However, because of Hollowell's long, lanky frame, there are many moving parts in his delivery, which render it difficult to repeat on a consistent basis. Though some scouts have concerns that Hollowell's mechanics will cause him to struggle with command and control, Hollowell has thrown both of his pitches for strikes since being drafted.

Further, Colorado has emphasized cleaning up Hollowell's delivery since draft day. Hollowell had a noticeable crouch in his delivery in college. However, Colorado has taught Hollowell to stand up tall on the mound, creating better leverage. The results have been noticeable and reports indicate that Hollowell has shown the ability to more consistently repeat his new delivery.

Though Hollowell has only pitched 18.2 innings at the Rookie-level, I think that he has the stuff to move quickly through the Rockies system. Hollowell's nasty fastball/slider combination is prototypical of a high-leverage reliever. If Hollowell can continue to refine his mechanics and throw strikes, he has a bright future pitching at the end of games in Colorado.

Outside of Daniel Bard, who will be 36 years old for most of the 2021 MLB season, the Rockies bullpen was atrocious in 2020. If I were to break out my crystal ball, I see fellow prospect Ben Bowden (#15) and Hollowell as the Rockies future eighth and ninth-inning options. With his size, arm strength and late-game mentality, Hollowell is a rare breed of pure reliever prospect and one of the few that I think warrants your attention in deep dynasty leagues.

Ryan Feltner, RHP  (#24)

Bats: R | Throws: R
Tools: 60 FB | 50 CH | 50 SL | 45 CNTRL
Age: 24
Highest Level: A
ETA: 2022

The Rockies drafted Ryan Feltner out of Ohio State, in the 4th round (126 overall) of the 2018 MLB draft.

Feltner dominated Pioneer League hitters in a small sample size during his 2018 professional debut. Over nine starts (30.2 innings), Feltner compiled an unbelievable 0.88 ERA and 0.65 WHIP. Further, Feltner displayed both elite strikeout stuff and command. Feltner posted an immaculate 36.1 K% and 3.7% BB% while holding hitters to a measly .157 BA against.

Despite a debut to dream on, Feltner struggled against more advanced competition at low-Class A during his first full season in 2019. Over 25 starts (119 innings), Feltner limped to a 9-9 record with a 5.07 ERA and 1.54 WHIP. Though, Feltner's 4.21 FIP reflects that he was the victim of some bad luck. In addition, Feltner saw his K% decrease to 21.8% and his BB% increase to 8.6%.

Although Feltner's 2019 numbers tell a rough story, he displayed noticeable improvement as the season went on. In Feltner's final 10 starts of the season, Feltner only had one outing with less than five innings and more than three runs (the same outing). Moreover, Feltner allowed only eight runs combined over his final five starts, going 4-1 over that span. The only loss came in a five-inning, two-run outing.

After a rocky 2019, Colorado coaches have praised Feltner for his work in refining his delivery during the pandemic. Feltner shortened his arm action and the results were evident immediately. According to Rockies farm director Zach Wilson during 2020 instructs, "[i]t was very, very clear from the moment [Feltner] stepped in there that everything he was working on and that we had been working on with him was not only taking hold but was really having some pretty dramatic positive results."

Feltner's shorter arm action has elevated his fastball velocity from 92-93 mph to 95-97 mph and allowed him to better command the pitch. In addition, Feltner has always possessed an above-average changeup with good fade that plays well off his fastball.

In the past, critics have knocked Feltner for his lack of a reliable third pitch to complement his solid fastball/changeup combination, which would heighten his level of bullpen risk.

However, Feltner's adjustments have also led to improvements in the consistency and effectiveness of his slider. Per Wilson, "[Feltner is] sitting 95-97 mph with a pretty nasty slider...[h]e's dominating down here." Feltner's slider is now up to 86-87 mph and displays much better late action than it has in the past. Further, reports indicate that Feltner's adjustments have also led to command gains, a welcome sight after his BB% swelled in 2019.

Now armed with an intriguing three-pitch mix and higher velocity, Feltner appears primed to breakout in 2021.

Feltner has filthy stuff. There is no doubt about it. Let's not forget how dominant he was during his 2018 debut. But for Feltner, it will come down to whether he can maintain his command gains over a full season. If he can, I think Feltner can rise quickly through a Rockies system that is thin on starters and prove to be a solid rotation piece by the end of 2022.

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1 comment

2021 Detroit Tigers Diamonds in the Rough - Fantasy Six Pack March 27, 2021 - 7:00 am

[…] Last time out, I took a look at some of the Colorado Rockies prospects. […]


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