The Level Changed Luis Hernández And It Did Not Change Josuar Gonzalez

The Giants ran a controlled experiment this summer and nobody in the organization meant to.

On July 24 they promoted Josuar Gonzalez and Luis Hernández to Low-A San Jose together. Same day, same clubhouse, same league, same ballparks, same bus rides, same pitchers. Both are shortstops. Both came out of Latin America as amateurs, Gonzalez from San Cristóbal in the Dominican Republic and Hernández from San Juan de los Morros in Venezuela. Both are teenagers, born fourteen months apart. Both played their first California League game on the night of July 25.

You could not design a cleaner test than that, and the reason it is clean is that it was an accident. Two subjects, one variable, and the variable is the level.

Four weeks in, the level has an opinion.

Gonzalez is hitting .379/.476/.609 in 21 games and 105 plate appearances through Saturday, when he went 4-for-5 with four runs batted in and two stolen bases in a 6-3 win at Lake Elsinore. Hernández is hitting .231/.276/.319 in 20 games and 98 plate appearances. That is 490 points of OPS between two men who got dressed in the same room every night for a month.

Now the part where I take most of it back.

Gonzalez has a .463 batting average on balls in play. That is not a skill. That is not even mostly a skill. San Jose as a team is at .342, and Gonzalez is 121 points above his own teammates. Balls in play are the noisiest thing in baseball over four weeks, and a hitting line built on top of one is a rented apartment.

So take it away and see what is underneath. He has 87 at-bats, 19 strikeouts, two home runs and a sacrifice fly, which leaves 67 balls he actually put in play. Give him his own team's rate on those 67 instead of his own, keep the walks and the strikeouts and the homers exactly where they are, and he hits .287 with a .400 on-base percentage.

Which is still an 18-year-old in his first full-season league, hitting .287 and reaching base 40 percent of the time. Fine. Good, even. Not .379.

(That is my arithmetic and not a projection system's. Handing a player his own teammates' luck is a coin flip wearing a lab coat. It is also the most conservative version of him I know how to build, and he survives it.)

Do the same thing to Hernández and he goes from .231 to .253, because his own mark on balls in play is .311 and the correction runs in his favor rather than against it. He is not unlucky. He is just not hitting.

Anyway. Balls in play are where the noise lives, and walks and strikeouts are not balls in play. Nobody dives, nobody misplays the sun, nobody hits a rocket at a shortstop. A walk is a walk in the box score forever.

Gonzalez has walked in 15.2 percent of his plate appearances at San Jose and struck out in 18.1. Hernández has walked in 6.1 and struck out in 29.6.

And here is the number underneath all of it. In the Arizona Complex League this year, before either of them had seen a full-season pitching staff, Gonzalez walked at 16.4 percent and struck out at 20.5. Hernández walked at 11.0 percent and struck out at 16.7. Hernández had the better strike zone of the two. He struck out less often than Gonzalez did, in a sample nearly twice as large, 228 plate appearances against 122. Gonzalez had the better overall line, a .966 OPS against .917, and got it with a worse strikeout rate.

Then they both climbed a rung on the same afternoon, and Gonzalez's strike zone did not move at all. His walk rate went down a point and his strikeout rate went down two and a half, which is measurement noise wearing a suit. Hernández's walk rate was cut roughly in half and his strikeout rate went up thirteen points.

One of them noticed a change in the pitching and one of them did not. That is what the four weeks bought, and a hot streak cannot take it back.

The case for Hernández is real and it gets full size here rather than a nod, and the first line of it is the same list. Pipeline has him 27th in baseball, ten spots behind Gonzalez and inside the top thirty. It published that on August 16, when he was hitting .244 at San Jose with six walks against twenty-seven strikeouts, and ranked him there anyway. He is 17 years old and does not turn 18 until December. He is the younger of the two by fourteen months, and fourteen months is an enormous span at this age. This is his first professional season above the complex, and he got there by skipping nothing. Twenty games is twenty games. He hit .298/.382/.535 in the Arizona Complex League with 19 doubles, five triples and six home runs in 54 games, at 17, which is not the resume of a player who cannot hit.

He also has not batted since August 20. San Jose played on the 21st and won 21-2, then played on the 22nd and won 6-3, and he was not in either box score. He is listed as active on the club's roster and he is not on the injured list. Nobody has published a reason and I am not going to invent one.

Meanwhile the industry has been busy revising its opinion of the whole system in public. MLB Pipeline moved the Giants from 19th to 5th in its refreshed in-season farm rankings on August 16 and named Gonzalez as part of the reason. Pipeline has been rating farm systems since 2015 and San Francisco had never been higher than eighth, in mid-2021. Gonzalez is its No. 17 prospect in baseball. (A ranking is a shop revising its opinion of its own earlier opinion, which is worth roughly what you paid for it. The plate appearances underneath it are not.) MLB.com's write-up on him this weekend reaches for Francisco Lindor and José Reyes, which is an unreasonable thing to hang on an 18-year-old in braces and is not his fault.

He is also not on the California League batting leaderboard, because 105 plate appearances is nowhere near enough to qualify for it. The two men who do lead the league are hitting .339.

Thirteen regular-season games are left before September 6. One this afternoon at Lake Elsinore, then six at home against Visalia and six at Fresno, and the pitchers in all three places have now had a month of video on a switch-hitting shortstop who has taken sixteen walks in twenty-one games.

Then there is more of it, because San Jose won the North in the first half and is already in. The league has the Giants opening a Division Series on September 8 and hosting the tenth and the eleventh. The experiment runs past the end of the schedule.

The control group has not batted since Thursday.