Let’s start off with the fact that Jeremy Peña is a fan favorite. He was MVP of the 2022 World Series. That achievement will follow him forever. He has a personality and athletic ability that you root for.
However, so far, this season has been disappointing. Peña’s diminished offense plays a role in the periodically erratic team offense. Because Jeremy’s defense is important to the team’s performance, he has played in 91% of games, making his offensive slumps more notable.
The comparison below shows Jeremy Peña’s offensive summary stats for the 2022 regular season, the 2023 season, and in the past 28 days. (Note that OPS+ is expressed as a percent of league average hitting.)
(batting average, isolated power, OPS+)
2022 BA .253 / ISO .173 / OPS+ 101
2023 BA .236 / ISO .132 / OPS+ 83
Last 28 Days BA .195 / ISO .065 / OPS+ 40
The OPS+ for the 2023 season is very bad—not just 17 points below the league average hitter, but also 11 points below the average shortstop (a position that tends toward weaker hitters). Over the last 28 days, Peña’s OPS+ has cratered. I have focused on the Isolated Power stat (ISO) because his power has fallen severely compared to 2022. For all of Pena’s offensive flaws, the one redeeming characteristic in 2022 was above-average power for a shortstop. But so far, we haven’t seen that ISO.
If you want to see a glimpse of hope, Peña’s OPS+ over the last seven days (84) is about equal to his season OPS+. This is due to two two-hit days against the Rays and one 2 hit, 2 walk day against the Guardians. It’s difficult to say whether this is the beginning of a rebound—particularly if the rebound is to 14% below average. But any offensive resurgence has to start somewhere.
You can look at Peña’s player page at Baseball Savant and see much the same story. I won’t repeat all the details of the summary percentile ranking box—but it’s sufficient to point out that he is below average for everything except sprint speed and maximum exit velocity. Notably, he is in the bottom 10% in chase rate and the bottom 20% in SLG.
Why has Peña’s power dropped from 2022 to 2023? His average exit velocity is well below the league average, but it is about the same as in 2022. His sweet spot percentage is about the same as last year. But his launch angle has dropped significantly (8.7 to 6.0), meaning he is hitting too many ground balls. Probably more telling is that Peña’s Barrel% has dropped from well above average in 2022 (9.7) to well below average in 2023 (4.6). Barrels are batted balls with the optimal combination of launch angle and exit velocity. Presumably, this partially explains the loss of extra-base power (ISO).
The FanGraphs’ rest of season projections indicate a potential rebound for Peña, with a projected wRC+ of 94 and 6 HRs. The HR projection would result in 16 HRs vs. 22 in 2022. While this would still be viewed as a step back from 2022, it would be welcome, given the last month.
I don’t usually dwell on batting order decisions—primarily because, in most cases, the impact on team run scoring is minimal. However, sometimes the circumstances make it seem relevant. In recent days, Peña has batted in the No. 2 slot. Two factors make me question this decision. First, based on studies of optimal batting orders, the No. 2 slot is perhaps the most important for team scoring. And, second, Peña is in the midst of a deep offensive slump.
Most sabermetrics articles use The Book: Playing the Percentages in Baseball (Tango, Lichtman, Dolphin) to discuss the optimized batting order. The two best hitters should be in the No. 2 and No. 4 slots, with the better OBP batter in the No. 2 slot. Studies performed for The Book found that the No. 2 and No. 4 slot usually faced the most critical runner on-base situations but that the No. 2 slot also has more plate appearances over the season and, therefore, should lean toward hitters with on-base skills.
Peña is currently not well equipped for the No. 2 role by this criteria. Furthermore, Peña swings at the first pitch 44% of the time, which is about 50% more than the average batter. First-pitch swings are inversely correlated with walks—meaning that it’s not a characteristic that is usually associated with on-base skill. Pena’s plate discipline is not well suited to the No. 2 slot.
In the past, Manager Dusty Baker has justified putting Peña in the No. 2 slot in order to get more fastballs thrown to him. And that is a logical reason, given that Peña does not hit well against breaking and off-speed pitches. But it depends on Peña showing more plate discipline and patience.
Some fans argue that Peña should hit in the No. 2 slot because his results were better when Dusty moved him there last year. I am skeptical of that view, partly due to the small sample sizes for batting order positions. Furthermore, there isn’t much sabermetric evidence that placement in the batting order strongly affects a batter’s hitting. If you are willing to overlook the small sample sizes, Peña actually has his highest OPS in the No. 8 slot this season.
Setting aside the effect on Peña’s performance, moving him out of the 2-slot and into the 8 or 9 positions would improve team run scoring by allowing the best hitters (i.e., Tucker, Bregman, Alvarez) to move up one slot in the order.
This is an article about Peña’s offense, so why would I discuss his defense? The main reason for keeping Peña in the lineup as much as possible is his superior defense at the most important defensive position. However, according to the advanced metrics, Peña has shown a decline in defense compared to 2022.
According to DRS (defensive runs saved), Peña’s +16 runs saved in 2022 have declined to +1 run saved in 2023. Peña’s defensive ranking at shortstop, according to DRS, had declined from 1st to 16th. Savant’s Outs Above Average (OAA) shows that Peña has declined to a -1 run. This would make him tied for the No. 32 ranking at shortstop.
My personal view is that Peña’s defensive skills still make him critical to the team’s success. But as his defensive metrics decline, his defensive advantage over bench players Dubon and Kessinger also decreases. At this point, I don’t think it makes sense for either bench player to get more playing time at shortstop. Dubón has been slumping on offense too. And projections would indicate that Kessinger is a downgrade on both offense and defense.
Hopefully, Peña can rebound on both offense and defense.