Does Framber Valdez Warrant a Five Man Infield?

Framber Valdez
Peter Aiken-USA TODAY Sports

FanGraphs readers are a smart bunch. Though the comments can sometimes unravel into a series of shouting matches, the usual atmosphere is encouraging and collegial. For example, here’s a thought-provoking question I received a few weeks ago and my reply to it:

This is from an article I wrote about Framber Valdez and how he was on pace to shatter his own historic groundball-to-fly ball ratio. A five-man infield in any other circumstance would be out of the question, but consider just how many grounders Valdez generates. Among starters with a minimum of 200 innings pitched since 2020, he’s first in groundball rate (66.7%) by a wide, wide margin. With so few balls heading towards the outfield, does it make sense to reinforce the infield instead? It’s an intriguing inquiry, one that I promised would receive an answer. So here goes!

First, let’s try a naive estimate of how five infielders would aid (or hinder) Valdez. Imagine that since the beginning of this season, the Astros had rolled out a five-man infield for their young lefty whenever possible. By creating an alternate reality of sorts, we can work out how much a difference a persistent five-man infield would have made compared to what the Astros have actually implemented so far.

But what does a five-man infield look like, anyways? In my head, it’d resemble a standard infield alignment but with one extra fielder to reinforce the batter’s pull side. Basically, it’s a shift with none of its drawbacks. The closest thing I could find to a real-life example was this bizarre shift from the Dodgers against Eric Hosmer:

It’s not perfect, but you get the idea.

Excluding one bunt, Valdez has allowed 26 hits on groundballs as of this writing. How many of them would a five-man infield have prevented? To find out, I went ahead and watched every single one on Baseball Savant. Some, like a Jo Adell double down the line, were simply out of the Astros’ reach. Others consisted of relatively easy outs that the infielders bobbled but were deemed base hits. A small portion of them were absolute rockets that pierced through the shifted infield.

All in all, these are instances where a fifth infielder wouldn’t have been much help. Add them up, and the final tally is 18. The remaining eight fell into one of two groups: (1) a ball that sneaked past a gap a fifth infielder could have blocked, or (2) a ball hit toward the open side of an infield shift. It’s not a whole lot to save, but those are eight entire hits we’re pretty sure a stronger, five-man infield could eliminate. All of them were singles, and the run value of a single relative to an out this season is 0.70; that works out to 5.6 fewer runs allowed by Valdez and the Astros.

There’s a gigantic cost to running a five-man infield, though. While shading your outfielders to the pull side is in vogue, we’ll assume the Astros are creating a vacancy in center, with only left and right occupied. In that case, any ball that would have been a single under the watchful eye of the centerfielder becomes at least a double. Any ball that would have been an out… also becomes at least a double. You can see why bringing in a fifth infielder has long been reserved for extremely specific situations, such as when allowing the runner on third to score instantly loses the game. It’s generally not worth it.

Thankfully, Valdez is a cheat code. This season, he’s given up merely eight straightaway line drives and one straightaway fly ball. I’m not going to try to guess what percentage of them would end up triples without a centerfielder; for now, let’s assume they’re all doubles. From here, figuring out how many runs Valdez and the Astros would stand to lose from a five-man infield is simple: Subtract the run value of a double from the run value of a real-life out or single, then add up the negative values. That works out to negative 5.5 runs, for a net gain of one-tenth of a run. Hooray! It’s by the slimmest of margins, but with our built-in assumptions, implementing a five-man infield would have theoretically done more harm than good.

Is that a silly conclusion? Definitely; when a single triple reverses it, you know it’s flimsy. So this time, let’s attempt something more rigorous. There’s small-sample weirdness we can amend, such as the fact that only one fly ball ended up in center. Instead, let’s use a set of broader numbers taken from Valdez’s career, the Astros’ overall tendencies, and the league as a whole. Here’s an example of information of we’d want to incorporate:

Valdez’s Batted Ball Directions by Type
Batted Ball Type Pull% Straightaway% Opposite%
Ground 45.1% 41.9% 13.0%
Air 27.9% 31.1% 41.1%
SOURCE: Baseball Savant
Ground = groundballs
Air = line drive and fly balls, excluding popups

These numbers represent Valdez’s entire career. As a side note, if you wondered why the Astros like to use Yordan Alvarez in left field when he pitches, there’s your answer. Valdez doesn’t allow a lot of airborne contact to begin with, but when he does, most of it doesn’t go to the pull side. And since righties are overwhelmingly up against Valdez, that means Alvarez is provided with the conditions to do as little outfield work as possible. Though Valdez isn’t an outlier in this regard — hitters overall pull around a third of their balls in the air — it still seems meaningful to use his rates rather than the league’s.

This also gave me the idea to abandon the pull side of the outfield. Think about it: Because pulled balls are more dangerous (i.e. average a higher wOBA) than their straightaway and opposite counterparts, the opportunity cost in electing for two outfielders actually decreases. That’s our set-up, then: a shifted infield with an extra defender, followed by two outfielders to focus on the non-pull areas of the outfield.

Next, I also considered various handedness splits. Unlike most pitchers, Valdez runs a higher groundball rate against batters of the opposite handedness and not the other way around; per Baseball Savant, he’s at 67.2% against righties and 61.3% against lefties in his career, though I’m not sure why this is the case. Maybe it’s because he faces so many darn righties — 78.1% of the time, to be exact. In addition, the Astros this season have used an infield shift against 19.2% of those righty batters, a rate that skyrockets to 78.2% against lefty batters.

Phew, that’s a lot of percentages. But now we can piece together a serious estimation of a Valdez-led five-man infield. Based on the aforementioned splits, we can say that for every 1,000 batted balls Valdez allows, 800 would have been to right-handed hitters (this is the only time I’ll round up or down). Roughly 538 of them would have ended up on the ground: 243 pulled, 225 up the middle, and 70 the other way. Here is where the five-man infield comes into play. Knowing the Astros’ tendencies, we’d expect 47 pulled grounders to run into the shift and return, on average, a .154 wOBA, with the rest returning a .226 wOBA (based on Statcast data since 2016). With an extra infielder, however, we’d expect all 243 grounders to return a .154 wOBA — exactly the benefit of a five-man infield. Repeat the process for all batted ball directions and left-handed hitters, and that’s part one finished.

As for the 249 fly balls — the other 13 are presumed popups — we just need to adjust the pulled variety. In 2022, hitters are mustering a .527 wOBA on pulled balls put into play in the air. But what if a fielder weren’t there to interfere? For the sake of simplicity and giving Valdez optimistic odds, let’s say every pulled fly ball is a double; this season, that translates to 1.271 wOBA. It’s quite the price to pay, and that’s after minimizing it.

Now, the million-dollar question: Does a five-man infield save more runs by preventing groundball hits than it loses by allowing any pulled fly ball to become a double? The answer is… no. It’s not even particularly close: Over a thousand batted balls, Valdez and the Astros would stand to lose 27.9 runs. Ouch! What’s worse, that figure exists in a fictional universe where triples are unheard of. As tempting as the idea sounds, “supporting” Valdez with an additional infielder hemorrhages a surprising number of runs. Dang it, math, you’re ruining all the fun!

But hang on. In reality, it’d be foolish for the Astros to bolster the infield against every single hitter who comes up to bat against Valdez. Fly ball hitters probably aren’t worth the effort, but it’s reasonable that groundball hitters are. So I asked myself another question: If Valdez is guaranteed a groundball rate of 80%, would that make a five-man infield viable? It’s an indirect but sensible way of figuring out whether shifting against solely groundball hitters is our path moving forward.

Unfortunately, the math once again brings the party to a halt. This time, Valdez and the Astros would stand to lose 9.5 runs — a markedly huge improvement, but one that isn’t enough to escape the red. It seems like the breakeven point is somewhere north of 90% groundballs, which is disappointing to say the least. Pretty much the only scenario that would warrant a five-man infield is if someone like Eric Homser stepped up to the plate versus Valdez, which is nothing new; the Dodgers did that three years ago with sinker enthusiast Adam Kolarek pitching.

Contrary to what you might think, Valdez’s extreme profile doesn’t give him much of a leg up in the five-man infield calculus; the complete absence of an outfielder is just too damaging. Teams can live without an infielder because grounders are relatively harmless, but the same can’t be said about outfielders and fly balls.

Still, I’d love to see the Astros roll out a five-man infield at some point with Valdez on the bump. Reason number one is that I’m a sucker for weird baseball strategy, but reason number two is that there likely are a few instances where the math works in their favor, albeit ever-so-slightly. Hey, just for fun, let’s use that 80% groundball rate again, but in tandem with DJ LeMahieu’s pull rate on fly balls and line drives since joining the Yankees in 2019: 13.8%. That changes everything: Instead of losing runs, the Astros are now saving 4.5 runs per one thousand batted balls. Of course, real-life LeMahieu wouldn’t hit so many grounders. But if the Astros ever find a combination of extreme groundball-hitting, pull-aversion, and Framber Valdez, well, they might have something to consider.

Statistics in this article are through games of June 8.

Justin is a contributor at FanGraphs. His previous work can be found at Prospects365 and Dodgers Digest. His less serious work can be found on Twitter @justinochoi.

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1 year ago

Let’s push this farther: How good do the two outfielders have to be defensively to break even? Let’s say the Astros kept Myles Straw and played Jose Siri next to him in the outfield. Together they’ve been worth about 10 OAA in only about 715 innings this year. If I’m not mistaken that prorates out to about 20 OAA over the year (10*162*9/715). Is that good enough? If not, how good do your two remaining outfielders have to make a third outfielder (mostly) superfluous?

Joe Joemember
1 year ago
Reply to  sadtrombone

Barry Allen, Wally West would work.