The Rockies have a roster—and in particular an outfield—full of left-handed hitters. Carlos Gonzáles, Gerardo Parra, Charlie Blackmon, and David Dahl are all left-handed, and the Rockies have regularly placed utilityman Pat Valaika in the starting lineup against lefties to avoid left-on-left matchups. Earlier this year, the Rockies demoted Mike Tauchmann and called up Noel Cuevas, presumably because (in addition to Tauchmann’s struggles) Cuevas provided a much-needed right-handed bat off the bench.
Yet while all this suggests that the Rockies should be more successful against righties than lefties, the reverse is true. The Rockies are below average (20th) in the league against left-handed pitching, with a wRC+ of 93. Against right-handed pitching, the team is dead last, with an atrocious wRC+ of 65.
What’s going on?
Let’s take a look at the Rockies versus lefties, minimum 20 PA:
Rockies v. LHP
| Name | PA % in 2018 | 2018 wRC+ | 3-Year wRC+ Average | Difference |
|---|---|---|---|---|
| Name | PA % in 2018 | 2018 wRC+ | 3-Year wRC+ Average | Difference |
| Trevor Story | 11.30% | 134 | 144 | -10 |
| Nolan Arenado | 10.46% | 221 | 136 | 85 |
| Charlie Blackmon | 10.04% | 172 | 112 | 60 |
| Ian Desmond | 10.04% | 128 | 102 | 26 |
| DJ LeMahieu | 9.00% | 182 | 123 | 59 |
| Chris Iannetta | 8.58% | 80 | 122 | -42 |
| Gerardo Parra | 7.11% | 75 | 76 | -1 |
| Carlos Gonzalez | 6.49% | 0 | 49 | -49 |
| Pat Valaika | 6.90% | -37 | 120 | -157 |
On the left is the percentage of plate appearances each player has versus left-handed pitching; in other words, Trevor Story has accounted for 11% of the team’s total plate appearances versus lefties. Next is each player’s wRC+ against lefties this year, then their three-year wRC+ against lefties, and then the difference between their performance this year and their three-year average. Beware small sample sizes: for players like Pat Valaika, the three-year average doesn’t mean much.
A few things stand out about this table. The first and most obvious thing is that the five players who account for the most plate appearances versus left-handed pitching all have a wRC+ above 100. There are several players with below-average numbers against lefties this year—González and Valaika stand out—but they simply haven’t played as much and only account for about 13% of the team’s at-bats.
The other thing that stands out is that the players who see lefties the most are almost all overachieving right now—and several players are really overachieving. Nolan Arenado, Charlie Blackmon, and DJ LeMahieu are all sporting a wRC+ of over 50 points higher than their career numbers.
In Nolan’s case, that might be sustainable—he had a wRC+ of 220 (!) versus lefties last year—but an increase that large is probably unsustainable across the board. You may not be used to hearing “Rockies offense” and “overachieving” in the same sentence this year, but that’s exactly what the team has been doing against left-handed pitching thus far.
Now let’s look at how the team fares against righties:
Rockies v. RHP
| Name | PA % in 2018 | 2018 wRC+ | 3-Year wRC+ Average | Difference |
|---|---|---|---|---|
| Name | PA % in 2018 | 2018 wRC+ | 3-Year wRC+ Average | Difference |
| Trevor Story | 11.01% | 76 | 82 | -6 |
| Charlie Blackmon | 10.24% | 155 | 132 | 23 |
| DJ LeMahieu | 9.86% | 93 | 98 | -5 |
| Nolan Arenado | 9.35% | 117 | 122 | -5 |
| Ian Desmond | 9.35% | -31 | 85 | -116 |
| Gerardo Parra | 8.58% | 56 | 94 | -38 |
| Carlos Gonzalez | 7.04% | 79 | 125 | -46 |
| Chris Iannetta | 6.66% | 69 | 76 | -7 |
| Ryan McMahon | 6.15% | 18 | 68 | -50 |
| Tony Wolters | 4.74% | -7 | 70 | -77 |
| Pat Valaika | 3.97% | -12 | 68 | -80 |
| David Dahl | 3.07% | 252 | 122 | 130 |
The takeaways here are slightly different. Nobody is significantly overachieving, although Desmond, Wolters, and Valaika are significantly underachieving, as each player currently has a wRC+ of fifty points less than their three-year average. Right behind them are Parra and González, who are over thirty points lower than usual. Again, beware the small sample sizes for (especially) Valaika and McMahon.
It may be tempting to conclude that the Rockies are merely overachieving versus lefties and underachieving versus righties, but that’s not exactly right. Unfortunately, the players who are overachieving account for more of the team’s at-bats than those who are underachieving.
Specifically, the Rockies are drastically overachieving (a wRC+ difference of over 50%) in 29% of their at-bats against left-handed pitching, while they’re drastically underachieving in just 18% of their at-bats against righties. So, to be precise, the Rockies are overachieving versus lefties and underachieving versus righties, but they’re overachieving in more at-bats than they’re underachieving.
Of course, there are some reasons for optimism. As bad as Desmond has been, he has been uncharacteristically awful against righties, and yesterday’s game offers some hope that a course-correction might be in order. And even if Desmond doesn’t improve, the Rockies should do considerably better against righties with David Dahl in the lineup.
But these tables also illustrate the problem with the Rockies’ overabundance of left-handed outfielders. Four of the top six hitters against left-handers over the last three years are outfielders—Parra, CarGo, Chuck, and Dahl. If the Rockies could allocate their plate appearances versus righties to favor those four, they’d improve. Unfortunately for the team, most major league teams have three outfielders, not four.
What should the Rockies do about this problem? I’ll keep these recommendations in the realm of the reasonable—i.e., within the current 25-man roster:
1. Thou shalt not sit David Dahl, especially against righties
Keeping Dahl out of the lineup on Friday and Saturday was inexcusable. Dahl should start every day. If, for some reason, Dahl isn’t going to start every day, he should at least start against right-handed pitchers. Dahl is probably the Rockies fourth-best overall hitter—against righties, he’s the third-best.
2. Play Gerardo Parra at first-base against righties
Yes, I know, there’s a time-honored tradition of putting people at first-base who don’t belong anywhere else. I wish we had a real first-baseman too. If you want to make the team better, you should convince another team that they need some leadership, make a few trades, and call up Raimel Tapia and Ryan McMahon. But if you can’t (or won’t) do that, you should play Parra at first against righties.
Desmond’s retooled swing has resulted in some drastic platoon splits. Unless last night was the start of a turnaround (and nobody should believe that until he starts to have more good games than bad), the Rockies need to find a way to take Desmond (-31 wRC+) and Pat Valaika (-12 wRC+) out of the starting lineup when a right-hander is on the mound. There’s an obvious defensive risk putting Parra at first, but hey, he’s not exactly replacing a gold glover either.
3. Send down Pat Valaika, or at least confine him to pinch-hitting
I know—I said I would stay within the confines of the active roster. But as these numbers show, Valaika has the dubious honor of being the only player with a negative wRC+ against both righties and lefties. Patty Barrels was fantastic last year, but at this point it’s clear that he needs a break.
Will these suggestions fix the Rockies offense? Not entirely. Among other things, this breakdown illustrates a simple truth: The Rockies’ right-handed hitters are generally better than their left-handed ones. The fact that González and Parra are left-handed is a problem, sure, but the bigger problem is that they’re just not that good anymore.
For now, though, the organization seems either committed to what they have, willing to wait, or too stubborn to cut bait. Even within those confines, the Rockies do have some options—and they should be willing to consider them to improve the team.