2018 Season Review: Middle Infielders

Wow, guys. What a crazy couple of weeks. I wrote my last 2018 review at the end of October. I was planning on writing this article soon after, then the you-know-what hit the fan with school and finals, and trying to find a job in baseball and planning for the Winter Meetings. Also, the Marlins were teasing the rebrand on their Instagram during that time and hype was at an all-time high, so I didn’t want to bum you guys out with retrospective pieces during a very forward-looking bubble of excitement.

Nonetheless, last year we didn’t get the season reviews done by the end of the year. With this article, and then outfielders, starting pitchers, and relief pitchers to cover, it’s going to be tough to do again. But I’ll be damned if I didn’t give it a shot. Let’s get into it.

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Looking Back

Around this time last year, the Marlins traded home-grown, grade-A, beefy-lad Giancarlo Stanton to the New York Yankees. In an attempt by new ownership to clear the books of the hastily made, long-term contracts forged in the waning minutes of the Loria Regime, the Marlins planned to dump most of the last ten years and $295 million on any contending team looking for a way to butcher their way into the playoffs. The Yankees bit, sending to the Marlins two young prospects in fireballer Jorge Guzmán and shortstop José Devers, along with Starlin Castro.

Although the first two names on that list were heralded as the tasty first course prepared by Chef Gary Denbo, the inclusion of Starlin Castro was puzzling. It was clear that this trade was two-parts-to-one a salary dump, so why did the Marlins insist on inheriting the ~$23 million remnants of Castro’s deal in return? It seemed counterintuitive to the Marlins cause, and most thought the Fish would end up flipping the 2017 All-Star for more prospects.

Steve Mitchell-USA TODAY Sports

Lo and behold, Castro was plugged into the 3-hole on Opening Day, and from there, he didn’t look back. Don Mattingly rode Castro to 154 games and 647 plate appearances in the second baseman’s age-28 season, and Castro answered the call.

All metrics check out at about average. His Weighted Runs Created Plus had his offensive efficiency at about 1% above average. The new toy on the table is Baseball Prospectus’ Deserved Runs Created Plus (dRC+), a proprietary retooling of wOBA and wRC+ that seeks to more accurately and precisely define a player’s offensive production by using more predictive, theoretical models in accounting for the value of a player’s expected contributions. After computing run values for all hitting events—from errors to home runs—it accounts for both park factors and the quality of the specific opposing pitcher to adjust the runs as needed. While the formula bears a striking resemblance to those of wOBA and wRC+, dRC+ is interesting because we don’t actually know (and may never know) how the sausage is made to get the final number. Just as teams have their own models for evaluating players, this is BP’s, and as of yet, they haven’t released how they weight their constituent parts. We just have to trust that the wizards behind the curtain are competently crunching the numbers.

And that was today’s stats talks; hopefully you haven’t left yet. In any event, the guys at BP had Castro hitting 8% below average this year and nine points under his wRC+. This is likely due to Castro’s lack of home runs, which BP has teased is a weighty part of their formula. dRC+ clearly has no pity for Castro’s hitting in home run black hole Marlins Park.

Really, the most spectacular numbers on Castro’s line are his games played and plate appearances. Castro is not by any means over the hill yet, but he isn’t a young buck either. He was traded from an ahead-of-schedule contending team to a squad deep in the rebuilding process, and yet, he came to the yard every day with his bat and glove and did his job. An fWAR of 2.3 is nothing to gawk at, but in terms of length and quality of production, if a couple other players followed suit, the Marlins could have surely tacked on a couple more dubs in 2018.

The only other player in this article that sampled close to Starlin Castro was Miguel Rojas. In his Arb-1 year, and with JT Riddle on the sideline, Rojas had the opportunity to seize the everyday shortstop role. He didn’t shrug from the task.

Rojas played much better as an everyday starting shortstop than he did when he was relegated back to utility-man status. Before JT Riddle returned, and in half as many games as after, Rojas slugged seven home runs on his way to a very respectable .415 slugging percentage. But whereas Rojas hit six percent better than average in the first half, he accrued just a 79 wRC+ after JT Riddle came off the DL.

Psyche is not an insignificant factor in a player’s performance; when you can come to the yard with job security, you’re likely to play more relaxed. That may have been the case in the first half of the season for Rojas.

The one constant in Rojas’ season was stout defense. In his 657 innings at shortstop last year, Rojas put up gaudy advanced fielding numbers, with 10 Defensive Runs Saved, and an Ultimate Zone Rating at 5.9 runs above average. Both of those were good enough for best of all Marlins position players, and 7th and 6th best among MLB shortstops, respectively.

Rojas racked up those totals by making the plays he needed to make, while also flaunting decent range. In terms of DRS, 8 of his 9 runs came from just Plays Made. Per UZR, Rojas saved 3.7 runs by preventing errors, while accruing 2.1 Range Runs Above Average in the process.

Fish Stripes original GIF

So why did Rojas get moved off of shortstop when JT Riddle returned? That’s a great question; the most likely answer is that JT Riddle is also a good defensive shortstop, and given his lack of utility when compared to Rojas, Rojas was the surer bet to move around. That’s exactly what happened when The Riddler returned from his torn-labrum injury at the end of May.

Unfortunately, Riddle couldn’t maintain the offensive success at shortstop that Rojas had created in his stead.

Nothing much to say that can’t be said by the numbers; although Riddle kept up the strong defense at the six, he never got it going at the dish. Ultimately, Riddle and Rojas put up identical wRC+, but Rojas got the nod in terms of dRC+, I can only assume because of the disparity in on-base percentage between the two. Riddle is another Marlin that needs to rethink his approach at the plate to cut down on strikeouts, increase walks, and improve his on-base percentage in 2019. Among those with at least 300 plate appearances, Riddle ranked 28th in BB/K Ratio among 38 MLB shortstops, and 6th of eight Marlins hitters.

Yadiel Rivera picked up the pieces after that. Rivera—who signed as a minor league free agent with the Marlins—was the 19th-ranked prospect in the Brewers’ 2015 Top 30, but dropped out in 2016 after playing 35 games for the Crew. Rivera sniffed just a game in Milwaukee in 2017 before he stepped into 111 games for the Miami Marlins in 2018.

Rivera’s numbers were by no stretch impressive. We’ll just leave it at this: his 37 wRC+ pegged him at 63% below average offensively. But it’s worth noting that the game total here is misleading; over those 111 games, Rivera accrued just 160 plate appearances, meaning that he was often used as just a pinch hitter. It’s so hard for players to produce without consistent playing time. Still, Rivera did come through with two walk-off hits for the Marlins this season.

Looking Forward

Barring any injuries or trades, Marlins fans can count on seeing JT Riddle and Starlin Castro up the middle for the Fish again, with Miguel Rojas peppered around the diamond as needed. If he plays the whole year, 2019 will be JT Riddle’s last year of total team control; Spotrac and Baseball-Reference both have him qualifying for arbitration as a Super-Two in 2020. Given the injury trouble and the lack of offensive production, Riddle shouldn’t see a substantial raise over the league minimum in 2019.

2019 will also be Starlin Castro’s last guaranteed year on his seven-year contract. The Cubs built into that contract a club option for 2020, but given that the Marlins will likely be calling up and acculturating their new wave of prospects then, it’s hard to say with confidence that the option will be picked up. Castro will have to prove his value in 2019 to earn the $16 million paycheck; otherwise, he’ll have to test the free agent market.

Miguel Rojas will be an Arb-2 player in 2019. While he earned just over a milly last year, he should get a decent raise in 2019. Brock Holt, another super-utility, earned $2.25 million in his Arb-2 year in 2018. On the other hand, shortstops Jordy Mercer and Jose Iglesias had very comparable seasons to that of Rojas before earning Arb-2 salaries over $4 million in 2017. If Rojas’ agents can convince an arbiter that he is primarily a shortstop (which shouldn’t be hard to do, given his defensive prowess there), Rojas can find his way into a relatively substantial bonus for 2019.

The fourth middle infielder position is very much in the air right now. Yadiel Rivera will have to show some pop in Spring Training if he wants to spend his nights on Miami Beach instead of Bourbon Street. Three names threaten his job security.

Deven Marrero and Dixon Machado are two veteran utility-men who were extended minor league contracts with spring training invites. Both players accrued just under 0 fWAR in 2018 in a little under half a season’s worth of games. Machado has the slight advantage as far as most-recent performances go, but overall, there is nothing to get excited about here. Both of these players will need to catch a second wind if they want to occupy meaningful posts for the Fish.

On the contrary, Isan Diaz is a name you should get excited about. The second biggest incoming name in the Christian Yelich trade, Diaz projects to take over at second base after Starlin Castro’s contract is up. Prospects Live compares Diaz to Marlins Legend Dan Uggla, predicting him to be a “three-true outcomes, bat-first keystone player” with a high floor and a ceiling as high as his K rate will allow it. Right now, Fangraphs places him as the best prospect in the system, while Prospects Live has him at third, Baseball Prospectus ranks him at fourth and Baseball America moves him down to eighth.

After tearing up Double-A in 83 games with the Jacksonville Jumbo Shrimp, Diaz didn’t exactly make the jump to Triple-A; as a Baby Cake, he posted an OBP/SLG/wOBA of .281/.358/.285. With that said, the 22 year-old has showed signs or promise in the Puerto Rican Winter League, where over 24 games, he has accrued a weighty AVG/OBP/SLG/OPS slash of .301/.362/.422/.783. Look for the Marlins to take their time with Diaz in Triple-A and let Rivera, Marrero, and Machado duke it out for the fourth spot, until Diaz becomes ready to learn the Jedi Way from Starlin Castro in The Bigs.

There always seems to be room for improvement in the middle infield. Next season is no exception; everyone has something to prove. It’s not too late for Starlin Castro to step up as a leader on the field and in the dugout. It’s not too late for JT Riddle to live up to his prospect hype and become a solid, all-around shortstop. And it’s not too late for Miguel Rojas to prove his worth as a full-season, everyday position player a la Javy Baez. If these players want to be included in the future of this club, it starts next season. They will have to overcome the struggle of platooning and getting inconsistent at-bats to show that they are worthy of permanent roles with the Marlins.

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Statistics and information courtesy of Fangraphs.com, Baseball-Reference.com, Baseballprospectus.com, and Spotrac.com.