Justin Verlander Has Altered His Pitch Usage Since Coming to Houston, and It's Done Wonders

Verlander has won all five of his starts since joining the Astros. How has he been so successful?

Keep things simple. Stick to the basics. Less is more.

However you want to describe it, Justin Verlander's success with his new club, the Houston Astros, basically boils down to this -- focusing on what works well and avoiding what does not.

End of the Line in Detroit

Prior to being dealt by the Detroit Tigers, Verlander was having an underwhelming season. He owned a 3.82 ERA with a 24.1% strikeout rate and a 9.2% walk rate (the current league average for those stats is 4.36, 21.6%, and 8.5%) in 172 innings pitched. Those certainly aren't bad numbers, but they're not elite, either. And actually, his 4.41 xFIP with Detroit was a bottom-25 mark for the season among qualified starters.

The numbers don't look great overall, but as mentioned early in September by our own John Stolnis, Verlander began to get hot around mid-July.

From John, "Over his last nine starts [July 19th to August 30th] he's been straight fire, with an ERA of 2.32, a strikeout rate of 30.5% and a walk rate of 5.4%."

So, Verlander was getting into a groove toward the tail end of his days as a Tiger, and since joining the Astros, things have actually gotten even better.

New Home, New Success

The sample size is much smaller, but in five starts with Houston, Verlander has been lights out. He owns a 1.06 ERA, 2.94 xFIP and a whopping 35.8% strikeout rate -- all while posting a minuscule 4.2% walk rate.

In other words, he's been an even better pitcher than the Astros thought they were getting based on his performance this season in Detroit.

Is there a reason Verlander has been so dominant since changing teams? I'm glad you asked, hypothetical reader.

In that same article previously referenced, John hinted at what appears to be a significant change and the main cause of Verlander's success. He started throwing his slider more frequently this season, and that has only increased since being traded.

In his 28 starts with Detroit, Verlander threw his fastball 58% of the time, his slider at 21.2%, his curve at 16.3%, and he barely threw a changeup (4.3%).

With Houston, Verlander has increased both the frequency of his fastball (59.3%) and his slider (24.3%), while throwing his two other pitches less. He's only thrown 14 change-ups in his five starts with the Astros, according to Brooks Baseball. It appears that Verlander has made a concerted effort to throw his two best pitches -- his fastball and his slider -- while only occasionally mixing in his other two.

And the result? Well, you already know that it's been highly successful.

Just nasty.

To further drive home the point, let's examine the plate discipline of Verlander's opponents.

Swing and a Miss

Whether he's been pitching for the Tigers or Astros, the frequency at which hitters swing at a Verlander offering, either outside the strike zone or inside the strike zone, has stayed almost identical this season. While hitters are not chasing more of his offerings, they are swinging through them at a significantly higher rate.

In his 28 starts with the Tigers, hitters made contact with a Verlander pitch that was outside of the strike zone 67.7% of the time. This number has plummeted to just 49.4% of the time since joining the Astros. To put that in perspective, only three qualified pitchers have a percentage lower than that for the season.

Simply put, hitters aren't chasing pitches at a higher frequency when facing Verlander, but they are failing to make contact when they do swing at pitches that would be balls. This helps explain why his swinging-strike rate has also increased, up to 14.2% with the Astros -- more than 4 percentage points higher than what it was in Detroit this season -- which would tie him with Clayton Kershaw for the fifth-best mark this year.

All of the swings and misses mean that hitters are also struggling to square up the ball against Verlander. His hard-hit rate allowed with Houston is 29.6% after he gave up hard-contact 35.2% of the time with Detroit. In all, opponents are hitting a mere .149 off Verlander since he moved to the Astros.

World Series Bound?

According to our metrics, both the Los Angeles Dodgers (25.2%) and Cleveland Indians (19.2%) have better odds of winning the World Series than the Astros (17.4%) do.

But if Verlander is able to continue pitching the way he has since coming to Houston, it'll make the Astros -- already a very good team before the trade -- that much tougher to beat in the playoffs with Verlander and 2015 Cy Young winner Dallas Keuchel leading the rotation.