White Sox Season Preview: Biggest Question Marks as the Season Begins

With Opening Day finally here, news of Eloy Jiménez’s diagnosis has gotten a promising 2021 season off to an ominous start.

The White Sox still have the potential for a deep run into the postseason, but the loss of Jiménez’s does leave their margin of error a lot thinner.

To be clear, every team in the major leagues have a level of variability in potential outcomes heading into the season. The high end of a team’s error bar represents their potential if everything breaks right, and the low end represents their floor if the wheels fall off completely. The White Sox are no exception.

Below are the biggest question marks this team is facing as the season begins. In order for the 2021 White Sox to reach their ceiling, the majority of these questions will need to be answered in a positive way.

Can Andrew Vaughn play left field?

Let’s start with the most timely question, and the one that could have lasting implications beyond just this year. It looks like Andrew Vaughn, who has not played the outfield in his entire college or minor league career, will open the season as a potential option in left field despite never having played the outfield beyond high school.

The good news is that the bar Vaughn must clear defensively to avoid being a downgrade is not exactly Torii Hunter. Tony La Russa claims that he expects above average defensive play out of Vaughn in left, which makes little sense considering the fact that prior to the injury of one of the worst defensive outfielders in the game, this move was not already on the table.

However, if Vaughn is somehow passable in the outfield, it would free up the DH spot for Zack Collins, who projects to have a bit more thump than any possible left field option.

Prediction: Vaughn is passable, but well below average defensively.

Is Zack Collins’ big spring a mirage?

Zack has put together an impressive spring performance. Always a three-true-outcomes hitter, Collins has struggled to consistently make contact against big league pitching in an extremely limited sample size. However, this spring, he had only six strikeouts in 44 at-bats, to go along with a .295/.380/.523 slash line. If he can continue this in the regular season, the DH at-bats against right-handed pitching seem to be his for the taking. In the best case scenario, Collins’ handedness and selective approach could help to balance a predominantly free-swinging and right-handed lineup.

However, as Daniel Victor notes, even at the minor league level, Collins has shown to be a streaky hitter. If Collins cools off at the wrong time, the Sox could find themselves in the all-too-familiar position of searching for consistency at the DH spot.

Prediction: Collins and Grandal finish with an identical OPS.

Which is the aberration — 2019 Yoán Moncada or 2020 Yoán Moncada?

When Yoán Moncada arrived in the big leagues, he was a highly-touted, extremely-toolsy prospect with major swing-and-miss concerns. For the first few years of his career, these concerns kept Moncada from truly becoming a superstar. In 2019, Moncada finally put it all together, as a change in approach led to a breakout 5+ WAR season that saw him set career highs across the board. While his BABIP was extremely high, the batted ball data showed that this was somewhat sustainable. Moncada ranked in the top 10% in exit velocity and hard hit percentage and top 15% in barrel percentage, all indicators of high expected batting average. However, in 2020, a shortened season (along with lingering COVID aftereffects) led to a return to a stat line similar to Moncada’s early years, with his average, on base, and slugging all dipping back to his 2017-18 norms. Surprisingly, though, although the stat line was similar, the way he arrived at that stat line was starkly different. In 2017-18, Moncada displayed top-tier exit velocity, but struck out way too much. In 2020, Moncada’s batted ball data fell off a cliff, with exit velocity and hard hit percentages cratering to career lows, by far.

Baseball Savant

Baseball Savant

Was the 2019 “breakout” a product of an unsustainable BABIP, or was the 2020 “regression” a result of a small sample size and lingering COVID aftereffects? The Sox need the latter to be the case, as Moncada may be the X-factor in the success of the 2021 season.

Prediction: Moncada ends up somewhere in between 2019 and 2020— .265/.350/.490 and 4.5 WAR.

Has Dylan Cease turned a corner?

Any time a pitcher flashes the tantalizing fastball/slider combination that Dylan Cease has in his arsenal, it is hard not to dream of his ceiling. However, so far in his MLB career, Cease has struggled significantly. First of all, the fastball command has been nonexistent. Secondly, Cease has dealt with spin efficiency issues on that fastball, leading to a pitch that, despite top-tier velocity, hitters have had little trouble squaring up. When you hear a fastball categorized as “flat,” this is what hitters mean. The addition of Ethan Katz, offseason videos showing improvement in that spin efficiency, and solid spring results have led many to consider Cease a potential breakout candidate.

However, Cease has looked good in short stints before. In order for him to solidify himself as a fixture in the rotation, he will need to show a consistency in command and results, something that he hasn’t quite been able to find yet at the big league level.

Prediction: Cease puts together a solid campaign, struggling to work deep into games but dramatically improving his strikeout rate and WHIP. With the White Sox bullpen depth, the troops are typically sent in to lock things down after five innings out of Cease.

Can Dallas Keuchel continue to buck the batted ball data?

Dallas Keuchel was absolutely outstanding in his first year in a Sox uniform, riding a 53% ground ball rate to a 1.99 ERA and fifth-place finish in the AL Cy Young voting. For all intents and purposes, White Sox fans have penciled him in for another stellar year in 2021. However, many of Keuchel’s underlying metrics point to potential for concern. Keuchel posted the lowest strikeout rate of his career in 2020, along with diminished velocity. For someone who doesn’t live on strikeouts and velocity, this is less important, but it makes his margin for error slimmer and the potential for batted ball luck variance greater. His home run/fly ball rate was 4.7%, easily the lowest in all of baseball. Home run/fly ball rate typically regresses to the mean over time, especially considering the fact that Keuchel’s career rate is a more typical 14.7%. His strand rate was also Top 10 in baseball, something that tends to regress as well. Most notably, the difference between his ERA of 1.99 and xERA of 4.30 is staggering. Many contact-oriented pitchers are able to sustain a lower ERA than the numbers expect, but not to that degree. Expected ERA also takes into account the quality of contact of each ball in play, including launch angle and exit velocity, so it is more predictive than simply taking FIP or a similar metric that penalizes a lack of strikeouts. Keuchel had an outstanding year in 2020. The White Sox need him to continue bucking the metrics and repeat that performance in 2021.

Prediction: Keuchel pitches like an average No. 3 starter, giving the White Sox a chance to win most starts while compiling an ERA around 4.00.

How long will Andrew Vaughn take to adjust to MLB pitching?

It says something about Andrew Vaughn’s hit tool that, having never played above High A, his ability to hit big league pitching is his SECOND biggest question mark heading into Opening Day. Vaughn is one of the most advanced hitting prospects in the game. Despite that, he missed out on valuable minor league at-bats in 2020 due to COVID. There is little to no precedent for this in baseball history, but reports from the alternate site last year were glowing, and the Sox think highly enough of him to challenge him with a major role out of the gate on a club with championship aspirations. Jumping straight from A-ball to the bigs, an adjustment period would be more than understandable. However, Vaughn providing offense out of the gate would go a long way towards replacing some of Jimenez’s lost production.

Prediction: Vaughn puts together a nice rookie season, slashing .270/.350/.450 and garnering Rookie of the Year consideration.

Is Luis Robert a very good player, or a superstar?

This all depends on the progression of his approach at the plate. If Robert repeats his 2020 efforts and shows no signs of development when it comes to pitch recognition, he will still be a very good player. The value that he brings with his defense and baserunning will always be there, and Robert was able to do enough damage at the plate to get by despite astronomical whiff and chase rates. However, if he begins to put things together at the plate and force pitchers to play to his strengths, he has the potential to be one of the most valuable players in the game.

In 2020, Robert was “a dangerous hitter, rather than a good hitter,” as Hawk Harrelson would say. Per Baseball Savant, the majority of his power output came against sliders, and he struggled to do damage against good fastballs. (Robert slugged just .276 vs 4-seam fastballs in 2020 vs. .657 on sliders.) However, sliders were also the pitch Robert chased the most and whiffed at the most. Based on this, if a pitcher executed his plan, Robert was out. However, if the pitcher hung something, Robert made him pay. He carried a barrel rate that was double the league average, but also an average exit velocity that was below league average.

That tells me a few things. First, Robert has excellent natural loft in his swing, as barrels need to meet a certain threshold for optimal launch angle in addition to exit velocity. This, along with top-tier maximum exit velocity, will allow him to consistently produce big power numbers throughout his major league career. How, then, is Robert’s average exit velocity so low? The answer is a large cluster of extremely low exit velocity balls in play. The average MLB first pitch swing rate was 29%. Robert’s was 54%. Pitchers began to use Robert’s aggressive tendencies against him, and he began putting too many “pitcher’s pitches” in play, leading to a lot of weak contact and sure outs. If Robert can begin to recognize pitches he can handle and take a more selective approach, he could be in for a huge season.

Prediction: Robert puts up the highest WAR of any White Sox position player, along with a 30-30 season.

Other major questions—