Reviewing First Half Rotation Matchup Luck

Now that the unofficial second half of the MLB season is underway, every team looks to reassess its approach as the non-waiver trade deadline nears. Underperforming teams look to become “sellers”, while teams confident in their playoff chances seek new infusion of talent as “buyers”. Part of a team’s prospective outlook is its remaining strength of schedule. Teams that over or under performed their talent due to the MLB schedule in the first half may look to benefit in the second half.

Having poor luck with the scheduling can cause an MLB team to underperform, but in addition to this there the luck involved with rotation scheduling. For instance, on two separate occasions, the Braves had to face a stretch of 4 #1 caliber pitchers in a row, and one of these occurred in a stretch of games where 10 of the 12 opposing starters were #1 caliber. Similar “luck” has also occurred for the Phillies and Diamondbacks so far this year. While in some instances the team handled it well, in others it caused extended overall down turns.

This luck applies to both the rotation scheduling of the other team, but also your own, and the disparity between the two. Let’s evaluate the relative strength of rotations that each team has faced over the first half of the season, and the disparity in the quality of their starter versus that of the opposing team.

Establishing Rotation Strength Relative to the League

To qualify a pitcher’s ability, we’ll sort the first half results of all pitchers with at least 3 starts, and sort by FIP into 5 quintiles (as each team has a 5-man rotation). For pitchers with less than 3 starts, we’ll call them a “Spot Starter” and rank them as a “6”. It’s important to note that in some very extreme cases (Tyson Ross, for example), the quality of the pitcher may be naturally higher than that of a spot starter, but due to injury they have not met the qualifications. On average, each team should have faced around 17 #1-5 pitchers each, and about 2 spot starters (it is for this reason we set the threshold at 3 starts to qualify).

Then, to see how lucky a team was with its rotation matchups, we’ll subtract the team’s starting pitcher rank from the opposing team starting pitcher’s rank. For example, if the opposing team is starting a #2 caliber starter, and the team is starting a #4 caliber pitcher, the “Starter Disparity” score will be “-2”. If the calibers were switched, then the team will have a Starter Disparity score of “2”. We will then average each team’s score across their first half, and rank by average Starter Disparity. The teams at the top of the list will have the best “luck” in rotation matchups, while the teams at the bottom will have the worst.

We’ll also display the number of games each team plays against each tier of pitcher caliber, and the winning percentage of the team against that tier. Below are the results:

Pitching Matchups
Average Starting Pitcher Disparity for each team for the first half of the 2016 season, listed alongside the number of games and winning percentage vs. each tier of pitcher.

Teams with High and Low Starter Disparity based on Rotation Matchup Luck

As we would expect, teams with very dominant pitching staffs appear in the top 10, while the teams toward the bottom have had lesser performing ones. Because the Cardinals are able to start a rotation of Adam Wainwright (#1), Carlos Martinez (#1), Michael Wacha (#2), Jaime Garcia (#2), and Mike Leake (#3), they are almost a quintile (rotation spot) and a half ahead of the opposing team in starter quality each game.

The Cubs and Mets can both say similar things when they are able to start the likes of Jake Arrieta (#1), Kyle Hendricks (#1), and Jon Lester (#2), or Matt Harvey (#1), Noah Syndergaard (#1), and Jacob deGrom (#1).

The Giants, Indians, and Nationals are also of note, with talent like Madison Bumgarner (#1), Johnny Cueto (#1), Corey Kluber (#1), Danny Salazar (#1), Stephen Strasburg (#1), and Max Scherzer (#2) on display.

On the other hand, teams without much rotation-level talent or have had a high number of spot starts (like the Reds, Brewers and Pirates), can be more than quintile behind the opposing team in quality.

Disclaimers to the Analysis

There are obviously a few caveats to this approach. For one, a team in a division with great pitching (like the Braves) that has to go against high caliber pitching (Mets, Nationals, and to a lesser extent, Phillies) will rank lower simply because they are expected to see higher-caliber pitching no matter what.

The results are also based on what has happened in the small sample size of this season, rather than the past few years, to attempt to gauge how unlucky a team is by running into “hot hands”. For instance, the recently traded Drew Pomeranz ranks as a #1, but in any other year, he would probably rank lower. But, a team would not want to run into Pomeranz this year, and for this reason it would be disingenuous to base his ranking on a previous season’s results.

Performance Against Opposing Teams Starters based on Rotation Strength

How unlucky a team is in its rotation scheduling is only one matter, however, as their actual performance against them matters too. For example, the Braves have seen more #1s than any other team in the league with 34, and posted a .294 winning percentage. In fact, all teams except for the Giants, Indians, Marlins, and Royals, posted a losing record against #1s. This number jumps from 4 to 10 winning records against #2s, and then escalates to 23 when you are looking at records against #5s.

This can double as a good way to evaluate a team’s hitters. Many of the teams toward the top obviously have high quality pitching, but they also win games against all levels of starters (the MLB-leading Giants have a .500 or better record against all 6 levels, for instance). On the other hand, the Phillies only have a winning record against #4s and spot starters, despite a pretty high starter differential. This speaks to their soft-hitting lineup, and explains their in-season fade after a hot start.

It can also serve as a good indication of which teams may need to upgrade their rotation heading into the trade deadline. For instance, teams like the Rangers or Pirates have an inherent disadvantage in every game in terms of starter quality. However, the Rangers specifically have fought against this and have managed a winning record against each spot in the rotation.

Teams Poised for a Deep MLB Playoff Run

It should come as no surprise that teams like the Cardinals, Cubs, Mets, Giants, and Indians appear toward the top of a starting pitching quality list. But not only do they rate highly in quality, but they also seem to have had a little luck on their side in terms rotation matchups with their opponents. On the contrary, seeing teams like the Braves or Reds toward the bottom isn’t all that revelatory. But what a team does against the pitching they do face can speak volumes. Teams that have winning records but only beat up on the back-end of other teams’ rotations may be hurt once the playoffs come around and all starters are high-quality. The chart above serves to paint a picture of how these teams may perform once the luck evens out for every team.

Readers, what do you think? Do teams really benefit from rotation matchup luck? Or do position player matchups matter more? Which players do you think teams will look to acquire at the trade deadline to help? Leave your thoughts in the comments below or on Twitter @SaberBallBlog. Don’t forget to subscribe to SaberBallBlog by clicking the green “Follow” button in the menu, and follow on Twitter for all of the latest updates on the MLB!

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7 thoughts on “Reviewing First Half Rotation Matchup Luck”

  1. Really interesting take Andrew! Crazy to think how low Miami is on the list and yet still well in the playoff race. I wonder if this list could determine who may need to trade for SP at the deadline too?

    Like

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