Is bringing up Edwin Diaz to the Seattle Mariners bullpen the best thing for his development?
Edwin Diaz was promoted Saturday from AA Jackson. He was the Mariners’ #2 overall prospect according to Baseball America after being drafted in the third round of the 2012 draft out of Puerto Rico.
Diaz’s “Stuff”
Diaz has an electric fastball that sits in the 93-95 MPH range as a starter, touching 98. In his move to the bullpen, that velocity has ticked up a touch, allowing him to sit more in the 96-98 range and reportedly touch triple digits on some scouts’ guns. This season he’s struck out 16 batters over 10 appearances.
The big key to Diaz’s ascension in the system, however, is his slider. It’s a filthy slider with a hard break that sits mid-80s and has great rotation, giving it the appearance of a fastball out of hand. As he matured into his body and developed that slider, he pushed forward, becoming the Mariners Minor League Pitcher of the Year last season as he struck out 145 over 141 innings.
Diaz has a change up that he can use, but it was very inconsistent last season. That led to the decision to start the season to move Diaz to the bullpen, in spite of his incredibly high ceiling as a starter.
Precedence: The Good
There are many examples of guys who came to the big leagues and did well after debuting as a reliever:
David Price – Price was called up as part of the Rays’ World Series run in 2008, and he threw out of the bullpen, making five appearances, one start in the regular season, and five appearances in the postseason out of the bullpen for the Rays as they worked toward the World Series. He moved to the rotation in 2009 and has made five All-Star teams and finished first or second in the Cy Young voting three times.
Adam Wainwright – Wainwright made his debut out of the bullpen in a September call-up in 2005, but the Cardinals pitched him in the bullpen all of the 2006 season, and he struck out 72 in 75 innings over 61 appearances. He was moved to the closer role for the playoffs that season, and helped St. Louis win the World Series as he pitched nine games without allowing a run, striking out 15 in 9.2 innings. He was moved to the rotation in 2007, and he’s been a three-time All-Star and finished in the top three of Cy Young voting four times since.
Johan Santana – The Twins acquired Santana as a Rule V pick, and in order to keep him on their team they used him in long relief for the next three seasons. In mid-2003, he moved to the rotation on a full-time basis, and Santana led the league in strikeouts three seasons in a row, winning two Cy Young awards and finishing in the top three of voting four times.
Derek Lowe – Lowe is a good example of a guy going from an extended run in the bullpen to a guy who became a very solid starter. Lowe was moved to the pen by the Red Sox upon his acquisition in 1997, and he spent the next four seasons as a reliever, making the All-Star game as Boston’s closer in 2000, leading the league in saves.
In 2002, Boston moved Lowe to the rotation, and while he was not an elite starter like others on this list, Lowe made at least 32 starts for 10 straight seasons as a starter, so he was very effective as a middle of the rotation, inning-eating sort of pitcher. He even won 21 games that first season as a starter in 2002 and finished third in Cy Young voting.
Precedence: The Bad
While there have definitely been examples of guys who came into the league and did very well starting off in a relief role, there are many who struggled to ever figure out their role on a pitching staff after their organizations bounced them between the bullpen and the rotation.
Joba Chamberlain – The burly Nebraska native came up to the Yankees bullpen in 2007 and was a revelation, making 19 appearances and striking out 34 hitters in the regular season before making two appearances in the postseason as a rookie. By 2009, the Yankees had moved him to the rotation full-time, and he made 31 starts, but they moved him to the bullpen for the playoffs. The next season, Chamberlain was thrown 73 times, and the inconsistency on his arm led to him breaking down with injuries over and over, shelving his once-promising career.
Kris Medlen – Medlen, in spite of his 5’10” (generously) stature, came to the show with a ton of natural talent, but the Braves simply never figured out how they wanted to use him. He never had a season where he made all starts or all relief appearances, frequently bounced back and forth between the rotation and the bullpen. In the end, it caused his elbow to snap – not once (in 2011), but twice (in 2014). Medlen has worked his way back to the Royals in their rotation, but his stuff has taken a major step back after his second surgery, and we may never see the pitcher Medlen could have been if he’d have been stuck in one role or the other.
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Josh Collmenter – While Collmenter has had relative success in both the rotation and in the bullpen, what he’s had is inconsistent roles. He’s finally returned to the Diamondbacks in the last week after missing time due to shoulder soreness. In each of his previous five seasons, he’s made 24 starts, 11 starts, 0 starts, 28 starts, and 12 starts, respectively, all while being on the big league club the whole time. Collmenter may not be a guy who would be an ace pitcher, but he certainly could be a Lowe-type of pitcher if he was ever allowed to settle into one role.
Justin Masterson – Masterson was a big-time prospect coming up with the Red Sox, ranked in the top 65 prospects in all of baseball by both Baseball America and Baseball Prospectus before the 2008 season. In that 2008 season, the Red Sox brought Masterson into their bullpen as a long man, and he threw 88.1 innings in 36 appearances (nine starts) in 2008. Boston did the same thing in 2009 before a trade to Cleveland, as he’d thrown 72 innings over 31 appearances (six starts) by the time he was traded on July 31st.
Masterson never did develop the ability to work through a lineup a third time at the major league level due to the constant shuffling between roles. He did find some success in Cleveland, but he never could get deep into ball games, and he went from an All-Star in 2013 to being released in August of 2015 due to injury and effectiveness issues. He’s trying to work his way back now in the Pittsburgh organization.
So What Does It All Mean For Diaz?
The Mariners have had pitching prospects recently struggle to reach the big league club with success, as highly regarded Danny Hultzen, James Paxton and Brandon Maurer all struggled at the big league level in the last few years. Even Taijuan Walker has scuffled at the major league level. This could be a way for the Mariners to get Diaz’s feet wet.
Many teams have been doing this recently. The Royals brought up Brandon Finnegan and used him in relief a matter of months after drafting him in the first round in 2014. The Braves recently moved highly touted prospect Tyrell Jenkins to the bullpen. The Astros took power-armed starter Michael Feliz and moved him to the bullpen to get him to the majors.
However, it would seem a waste of high-end talent if the Mariners were to keep Diaz in the bullpen, as successful as he could be in the role. With even minimal improvement in the change up, Diaz could profile as a top of the rotation starter, and those guys don’t just come along every day.