Justin Nicolino and the concern over prospect strikeouts

The Miami Marlins have a good amount of depth in the starting rotation between the team's four league-average or better starters from 2014 and the bevy of pitching talent in the minors. Sure, not everyone in the minors is expected to start eventually on a big league roster, and some of the players' ceilings are lower than others, but many of them have a decent chance at contributing should the Marlins feel like trading or demoting a rotation starter in the near future.

One of those prospects is Justin Nicolino. Nicolino won the 2014 Organizational Pitcher of the Year award and put up 170 1/3 strong innings, posting a 2.85 ERA and 3.43 FIP along the way. This was his second time going through Double-A Jacksonville, as he got 45 1/3 innings in 2012 late in the year. Those innings were not bad, as he put up a 3.02 FIP on the back of a 15.1 percent strikeout rate and a 5.9 percent walk rate. He just ended the year with an ugly 4.96 ERA in those innings.

But this year, he put up even better numbers! So much so that MLB.com's Joe Frisaro even said this in an article regarding the Marlins' 2015 left-handed starter options.

Nicolino was the ace on a team that won the Southern League championship. Ranked as Miami's No. 4 prospect, Nicolino may have moved ahead of [Andrew Heaney] in terms of being big league ready now.

I'm not ready to buy that yet. Why am I so concerned?

It would naturally be expected for Justin Nicolino to see his strikeout rate drop as he went up in subsequent levels, but the drop-off in 2014 was extreme. Nicolino got away with striking out just under 12 percent of batters faced, which is an extremely low number for any pitcher. He barely walked anyone, and by the sound of it he adhered to the Marlins' principle of pounding the strike zone, but the loss of strikeouts might point to an alarming issue with a lack of stuff.

Now, I've heard the counterargument that Miami hosts a bevy of starters right now who have low strikeout rates, in part because they all attack the strike zone and lack out-pitches that get whiffs. Each of Henderson Alvarez, Jarred Cosart, and Nathan Eovaldi have gotten away with getting outs in other ways. But none of those guys had a strikeout rate this low in 2014. Even Alvarez, who is the most dependent on contact with a high ground ball rate, struck out 14.4 percent of batters in 2014. In fact, the likely reason why the Marlins were able to acquire Alvarez after the 2012 season was that he had one of the worst strikeout campaigns in history and was at risk of losing a rotation spot, having posted a paltry 9.8 percent rate for Toronto in 2012.

Furthermore, while it is easy to say that the Marlins might tolerate a low strikeout pitcher, all of these starters posted lower-than-average strikeout rates as Major League starters. Each player had better strikeout rates as a minor leaguer at a similar level to Nicolino.

The drop-off from the strikeout rate each of those guys put up to the rate they put up two to four years later is around four percent. If Nicolino lost anything close to four percent on his career Double-A strikeout rate of 12.6 percent, he would be in the same disastrous, unsuccessful territory that Alvarez was in during the 2012 season.

Nicolino has to regain some of the strikeouts he has been losing over each level, because pitchers with low strikeout rates do not succeed in the majors. Here are the five starters with at least 300 innings since 2012 with the lowest strikeout rates in the majors.

It should be noted that three of those starters walked fewer than six percent of the hitters they faced as well, so they were not all completely terrible in terms of walk rates. But overall, only one of them (Alvarez) posted an ERA or FIP that was better than the Major League average throughout the time period. In fact, Alvarez's ERA is the only one among the ten lowest strikeout rates that was better than league average.

Alvarez is likely an outlier and someone who would be difficult to emulate. Even with Nicolino's decent ground ball rates, he would be hard-pressed to repeat Alvarez's oddity of a performance, and even then, Alvarez's best seasons have come after he regained his strikeout rates since that horrific 2012 campaign. The rest of those starters are replacement-level fodder, as the five pitchers combined averaged between one and 1.2 wins per 180 innings. That includes Alvarez's performance, which was significantly better than the rest of the players.

The Marlins should at least be somewhat concerned about the lack of strikeouts Nicolino showed last season. His play was excellent otherwise, meaning success could still be on the way, but there is just enough worry that he should be given time in Triple-A to see if those rates bounce back.