Once bitten, twice shy could provide a unique buying opportunity on one of baseball’s best closers over the last three seasons. When Edwin Díaz moved to the Mets via trade, things looked optimistic for him taking over the ninth inning on a team loaded with starting pitching. However, not much went right for Diaz in 2019. He set a career-high in blown saves with seven last season, which is less than optimal. Diaz also served up 15 home runs, a career-worst. Not exactly what the Mets had in mind when trading for the talented young closer.

It feels like Diaz should be older, but he will turn just 26 in March of 2020. Hidden beneath his bloated 5.59 ERA in 2019, Diaz recorded a 3.07 xFIP (17th-best among qualified relievers) and a 2.63 SIERA (tied for ninth). His 99 strikeouts ranked ninth among all relievers. So what went wrong?

For starters, health could be a contributing factor. On April 16th, reports surfaced about a bone spur in Diaz’s pitching elbow. Then, on July 31st, a separate report about bone chips in it as well. Noting Diaz owned a 6.65 ERA from April 29th on, check out his vertical release points by month during his career and focus on 2019 in this chart from BrooksBaseball.net:

In April, Diaz notched a release point akin to his career year in 2018. As the season progressed, his release point kept drifting downward perhaps contributing to his inflated ERA. This proves to be speculative, but could explain his down year.

Delving into his Statcast data, Diaz registered much better expected statistics compared to his actual. He did throw fewer sliders in 2019 than the prior season, which also aligns with some elbow discomfort. Taking out his actual numbers, it’s worth noting how Diaz’s expected numbers do not show much variance except for the expected slugging percentage against his slider along with the decreased strikeout ratio statistics:

  • 2019 Four-Seam - 65.8-percent usage, .189 xBA, .339 xSLG, .273 xwOBA, 41.5 strikeout percentage, 35.1-whiff percent
  • 2018 Four-Seam - 62.1-percent usage, .202 xBA, .294 xSLG, .259 xwOBA, 32.9 strikeout percentage, 30.8-whiff percent
  • 2019 Slider - 33.9-percent usage, .223 xBA, .403 xSLG, .272 xwOBA, 35.9 strikeout percentage, 30.8-whiff percent
  • 2018 Slider - 37.3-percent usage, .116 xBA, .185 xSLG, .168 xwOBA, 56.4 strikeout percentage, 53.8-whiff percent

During 2019, Diaz performed better with his fastball but cratered with the slider. Perhaps injury along with the different seams affected his best offering? It’s tough to speculate. But, any migration to the mean by his slider along with elite fastball velocity makes Diaz tough to overlook for 2020. Yes, risk lies within this portfolio. However, what relievers do not come with inherent risk in drafts?

Before diving into his projections, here’s a look at the arsenal of Diaz from last season. First, his pitch plot:

And for some clarity, his swinging strikes registered last season:

When Diaz works ahead in the count, his stuff can be devastating. In spite of his struggles in 2019, he notched strikeout a percentage of 39 and the fifth-best swinging strike percentage (17.8) among his peers. Diaz also recorded the eighth-lowest contact rate against (65-percent) but also yielded a 45.3-percent hard hit rate, which ranked in the bottom five. So, when Diaz missed, it seemed to be center cut, hence the 15 home runs. This also resonated in his batted ball events on Statcast in which his barrel percentage ballooned to 10.1-percent compared to 3.8-percent in 2018. Injury, Murphy’s Law or just a down year of regression worked against Diaz.

Over the last three years, Diaz owns a 3.50 ERA, 2.84 xFIP, 2.42 SIERA and 1.09 WHIP with last year’s 5.59 ERA along with a bloated 1.38 WHIP factored in. He’s saved 118 games the last three seasons with a 38.5-strikeout percentage, 17.7-percent swinging strike rate and 65.3-contact percent allowed. Not too shabby. If his elbow holds up and the slider returns, suddenly Diaz sits on the precipice of a rebound. Due to a terrible 2019, Diaz already set up to be a draft day value. Add in the Mets signing Dellin Betances and the price on Diaz could be more attractive.

Heed the reports of his elbow heading into the spring. If they trend to optimistic and Diaz adjusts to the new baseball, buy all the depressed shares on the talented closer. Yes, his control can be wonky at times in the regular season but it will only take migration to the mean with his slider to lead to a 35-plus save season. Steamer projects Edwin Díaz for four wins, 31 saves, 98 strikeouts versus 23 walks, a 2.90 ERA and 1.05 WHIP. All well within reach. In fact, if news on Diaz trends to the positive, he will be a top-five closer once again in 2020. Buy for the talent, profit on the reduced cost. Things change drastically year-to-year in the closer market.

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Statistical Credits:

BaseballSavant.com

Fangraphs.com

Steamerprojections.com

BrooksBaseball.net