Who is Reynaldo López?
It's time: The young righthander has shown flashes of brilliance, but needs to tighten up his out pitches to anchor himself in the future White Sox rotation. (Clinton Cole/South Side Hit Pen)
The story of Reynaldo López's 2019 season seems to be nearing a three-part act. This first half of the season, which totaled 98 innings, was beyond a disaster. Among qualified pitchers by the All-Star break (78 pitchers), López had the worst FIP in MLB at 5.79, the worst HR/9 given up, and a laughably low ground ball rate to go with it. In other words, he looked like a bust and there were a lot of these type of videos every outing:
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Reynaldo López, not doing real well in the first half of the season.
After turning in his last start of the first half, López vowed to be better. Fans mostly scoffed because whenever he did show the potential we all know he has, López would revert back to the pitcher some started to think belonged in the bullpen. But then, López backed up that talk and he looked like an actual starting pitcher, like the guy who was good down the stretch in 2018, with a multitude of devastating strikeouts like this:
López was cruising through six starts of fantastic baseball. He wasn't allowing home runs — just one in 38 innings — to go along with a 2.87 FIP. He had the fifth-best fWAR over that six-start span, with 1.3. Everything was working, and I mean everything.
The fastball gained a little over one mph in velocity, and López was much more crisp with his location. Though not perfect, it was much better than the first half of the season.
López's fastball placement to righties: first half of the year on the left, from July 14-August 10 on the right.
The heat map above and below is a pretty good indicator of López's success because he so heavily relies on the fastball. Over the year, he has used his four-seam 57.6% of the time per Baseball Savant. Against righties, as you can see above, López was leaving his fastball in probably the worst possible place — right in the middle of the zone — and that played a part in his dramatic increase in home runs allowed. During his stretch of great pitching, you can see that López's fastball location against righties started to move inside and a little up. Now, there are still too many fastballs in the heart of the zone, and that location does not allow many ground balls, but the move inside clearly was working.
López's fastball placement to lefties: first half of the year on the left, from July 14-August 10 on the right.
Against lefties, the fastball has been immensely more crisp as it falls in the top of the zone. Again, that's not really good placement to induce ground balls, but it is a much harder to hit fastball than what López was throwing in the first half. Also, again, the placement is moving more up and in; not perfect, but the fastball was devastating over that six-game stretch with the new and better zone placement. Using Pitch Info, López accumulated a 4.5 value rating with his fastball, seventh-best in MLB over that stretch.
But it's not really all about the fastball, even if Reylo seems to want it to be, all the time. In fact, in order for Reynaldo López to be successful he needs to execute and be confident in his change and slider.
Both pitches are important in different ways. López uses the slider predominantly against right-handed batters and the change (with a curve sprinkled in) against lefties. Unfortunately, the slider that López really developed and learned to handle last year was not being duplicated in the first half of 2019. The change, which was López's worst-rated pitch coming up in the minors, also took a huge dive during the first half of the year. So in effect, Lopez did not have his "out" pitches against both sides of the plate for the first half, for the most part (yes, there was that one 14-strikeout game, where everything clicked).
Because López uses the slider mostly against right-handed batters, if it isn't on, he will struggle mightily against them. The same thing happens with the change against lefties, and that failure of his out pitches has led to his inconsistent season. When a changeup or slider isn't good that day, L��pez's fastball usage skyrockets, which means more well-hit baseballs and more runs allowed.
So far in the second half, López has been much better, but he is still showing that he is far away from being a top-of-the-rotation starter.
López's first three games out of the break was the best stretch of pitching since last season. Why was it so good? Well, the fastball location we already discussed played a huge part, but the change and the slider also were fantastic. Using Pitch Info's value statistic, López's change and slider were positively rated in each game. That success with both pitches led to a 2.16 FIP and 3.06 xFIP over those 21 innings.
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The next three starts, though still good and much better compared to López's pre-July starts, were inconsistent because the off-speed and breaking pitches were not simultaneously good during the same start. One day, the change was great and López was confident in it, so he was much better against lefties that day — but the slider was bad or he was just not using it, so right-handed batters got to him, and vice-versa when the slider was good and the change was bad.
However, because at least one of his out pitches were good, López had good results. He had a 2.65 ERA from July 30 to August 10, but a peripheral stat "saw" a problem during that stretch, with a 6.19 xFIP.
That xFIP spelled doom, and over a two-start stretch from August 15-20, López reverted back to what he was in the first half of this season: bad. His FIP was 5.85, and he had an ERA at 6.35 (that should have been worse because of four unearned runs) over those two starts. The change was awful in the first start, and the slider did not have a positive impact. In the second start, López's change was better, but the curveball (the other pitch López uses against lefties) was terrible and the slider was also bad. So for the second straight start, López got crushed because his out pitches were not working against their respective batters.
To his credit, in his last start, López did rebound nicely, sort of. He went five no-hit innings because his fastball and slider combination was working very well. However, his changeup was so bad he only used it at a 2.5% rate, so he was really only throwing a fastball against lefties. Thankfully, the four Texas Rangers left-handed batters couldn't catch up to that fastball despite the team being able to get López into some pitch-count trouble.
What this boils down to is who is the real Reynaldo López? He has been extraordinarily inconsistent, so it is difficult to ascertain if López is making progress, or if he still is just a reliever playing starter. For the majority of this season, López has looked like a reliever, a guy who really only needs one or two pitches in any given at-bat. A starter needs at least three, and maybe even four, to be successful over six-plus innings, and Lopez hasn't shown he has that ability besides that three-game stretch from July 14-24. Even in the three-game stretch, López still has not been able to rediscover his curve.
But there is a glimmer of hope, because of what we have seen from Lucas Giolito.
When Giolito started to look like a better pitcher last season, the velocity on all of his pitches was up. That has happened with López this season, with the additional spin rate increases over each month of the season so far. The fastball averaged 94 mph in April and has now climbed to 96.8 mph in August. The change has gone from 82.9 mph to 85.5 mph, while the slider has also increased 3.4 mph over the season. López's changeup and slider are also moving differently in the second half, and they have been more steady as well.
Lopez's changeup has a horizontal break that is not fluctuating as much, which gives the impression it has been more crisp and repeatable than before. That usually means López has more of a feel for it and better command.
Though not as extreme as the off-speed pitch, López's slider also has not been fluctuating as much game-to-game in its vertical break lately. The break has also steadily gone up as well, from a -38-inch average in April to -34-inch average in August.
You can look at López in two ways after this. A positive spin is to say he is on an upswing, improving every month. The second, negative take is that it took López half a season to get where he needs to be, and he still has not reached his potential after 432 2/3 career innings.
At this point, López needs to continue this stretch of better baseball. He needs to show he can work consistently with his secondary pitches, like he has on occasion this season, and not just throw meatball fastballs like he did in the first half of 2019. He needs to better prepare himself in the offseason so it doesn't take half the year to get good.
Thankfully, White Sox fans have already seen a worst-to-near-first turnaround in just one offseason from Giolito. Now it needs to happen with López, because the White Sox need to start winning games.
I'm sure López will be on the roster the next time the White Sox make the playoffs, but what remains to be seen is whether he is in the rotation or the bullpen.
The sky is still the limit for this fireballer, but time is starting to become an enemy instead of an ally.