Has the Crackdown on Foreign Substances Hurt the Performance of Framber Valdez?

The Crackdown

On June 21st MLB umpires began inspecting pitchers for the use of foreign substances, long illegal but unofficially tolerated until recently.

The crackdown has had an impact on overall batting statistics, perhaps not as dramatic as some would have expected, but still significant.

Some pitchers have seen dramatic declines in performance. Gerrit Cole’s ERA before the crackdown was 2.31. In the three games since it is 6.46 with an xFIP of 4.59, almost two runs higher than before the crackdown. His overall fastball spin rate since the crackdown has declined almost 180 RPM, from 2533 to 2353. His breaking ball spin rate has declined 175 RPM, from 2753 to 2578.

What about Framber?

Just looking at the most obvious result-oriented statistics it’s about that bad, although before the crackdown we are dealing with a much smaller sample size due to Valdez’s finger injury.

In his five games before the substance crackdown, Valdez had a 1.67 ERA. In the three games since it is 5.00, but that is mostly due to one bad game on July 6th. Unlike Cole, Valdez’s peripherals remain intact, SIERA before: 3.21. After: 3.41. xFIP before: 3.26, After: 3.03.

Valdez’s BABIP was an unsustainable .230 before the crackdown. His luck has normalized since, with a .373 in his last three games bringing his season BABIP to .283. His season ERA is currently 2.86, still below his xERA of 3.29.

The Drop-in Framber’s Spin

What is somewhat troubling is the drop in spin rates on the fastball but even more so on the breaking balls. As the following chart shows, since 6/21 Valdez has lost about 200 RPM on the breaking ball since 2020, and about 100 on the fastball. Before 6/21/21 Valdez’s spin rate was almost unchanged from 2020. The change is not that much different than Cole’s, especially on the curve.

Does the Drop in Spin Matter?

How much has this change in spin affected the speed and trajectory of Valdez’s pitches? An analysis using Brooks Baseball measurements doesn’t show much difference before and after 6/21/21. Fastball horizontal and vertical movement is the same within about a ¼ of an inch. And velocity is the same, in fact, the 4-seam is actually one MPH faster at 92.90 MPH.

There is slightly more change in the curve. Velocity has dropped from 79.02 to 77.45 MPH. Both horizontal and vertical movement is also slightly down about a third of an inch. In the past when I have studied these kinds of changes it seems that a drop in curve velocity is usually accompanied by an increase in movement, although the tradeoff of speed for movement usually favors the hitter. (If someone with more expertise on this subject would like to differ with me on this feel free)

In this case, Valdez’s curve has lost spin, movement, and velocity. And yet, according to Brooks the BAA and SLG Against on the curve are better since June 21 than before. Batting average against before: .091. Since: .044.

Framber’s curve is still among the best in baseball. According to Fangraph’s Pitch Value rating, Valdez has the fifth most effective curve in all baseball rated at 3.53 for the season. This is just behind #s 2-4, but way behind #1 curveball thrower Jacob DeGrom, rated at 10.13.

Before the crackdown, Valdez’s curve was rated slightly lower, at 3.35, so it is hard to say the substance crackdown has hurt the Valdez curve even if it appears to have somewhat different characteristics.

It’s not the Curve, It’s the Sinker

What has gotten worse since the crackdown is the sinker. As with the four-seam, spin is down about 100 RPM, but unlike the four-seam and curve, the BAA against is way up since 6/21. Opponents were hitting .236 before 6/21 and are hitting .452 since. But again, there’s only a ¼ inch less difference in vertical and horizontal movement, normal variation, so how much is this change in batting average caused by less spin, and how much is just small sample size variation?

Earlier we saw how in general strikeout rates have dropped about one percent since the crackdown, and base on ball rates have increased about one-half percent. For Valdez, his strikeout rate has increased 1.3 percentage points since the crackdown to 23.4, but his walk rate has increased 2.2 percentage points to 9.1.

His strike % has decreased from 62.7% to 60.1% since the crackdown. So possibly the crackdown has affected Valdez’s command, especially of the sinker.

Or perhaps, his sinkerball problems and slightly decreased strike % are just small sample anomalies.

But it is a trend to watch. A little less spin, a little less movement, and a little less control could add up to a significant impact in the long term. Let’s wait and see.