Here are the lines over their last four starts of two starting pitchers who recently faced the Twins.
14.44 ERA, .423 BAA, 1.045 OPS
Starter 2: 26.1 IP, 5 R, 17 H, 15 SO, 9 BB,
1.71 ERA, .177 BAA, .533 OPS
Now, here are the lines for those same two starters in their starts against the Twins.
Starter 2: 7 IP, 6 R, 7 H, BB, 2 SO
Starter 1 is Levale Speigner, a rule 5 draft pick who had four extremely rocky starts before shutting down the Twins on Saturday. Starter 2 is John Lackey, who has been one of the better starting pitchers in the American League over the last two seasons (ERA+ 2005 – 122, 2006 – 123). Lackey has pitched very well thus far, but the Twins were able to get to him and avoid a sweep in Los Angeles last Wednesday. Anecdotally, this has seemed to be a pattern for the Twins this season. Whenever they face a struggling pitcher (probably young, especially left-handed) they seem to have enormous struggles putting up any kind of offense. I know it’s easy to remember getting only 2 hits off of a pitcher like Speigner, but if Minnesota had knocked out 7 or 8 hits in five innings and put some runs on the board, the game would have been quickly forgotten. Do the Twins actually struggle more against below average pitchers? Or is this a case of selective memory making a problem seem worse than it actually is?
To investigate that question, I looked at the opposing starting pitchers in the 63 games the Twins have played so far this year (through Wed.). For each pitcher I sampled the five starts before their outing against the Twins to get as good of an idea as possible of how they were doing around the time of their outing. Early in the season obviously there wouldn’t be five starts beforehand, so I used any starts before the Twins outing, then complemented with starts directly after the outing versus the Twins to get to five total starts. I calculated FIP (Fielding Independent Pitching) as well as the more conventional ERA statistic for the 5 starts. Then I calculated runs per nine innings and WHIP for the start against the Twins. (Note: Virgil Vazquez (Det.) only has one start on the season, and it came against the Twins. I have placed him in the highest FIP/ERA category when it came time to place him) The American League average for these four stats are FIP and ERA – 4.40, R/G – 4.71, WHIP – 1.39.
First, I split things up by pitchers who were above or below league average in their 5 surrounding starts. That gives:
|Surrounding FIP||Avg. FIP||R/9 v. Twins||WHIP v. Twins|
|Surrounding ERA||Avg. ERA||R/9 v. Twins||WHIP v. Twins|
That table seems to indicate that the Twins are pretty much following the expected trend, they’re hitting the “worse” pitchers harder by both measures than the pitchers who had enjoyed more recent success. However, it is true that with both FIP and ERA, the runs produced by the Twins were above the levels previously observed in the more successful pitchers and below the levels of the less successful hurlers. Not quite the pronounced effect as my frustration would lead me to believe, but it’s a start.
Breaking it down further:
|Surrounding FIP||Starts||Avg. FIP||R/9 v. Twins||WHIP v. Twins|
|3.80 – 4.40||16||4.18||4.40||1.19|
|4.40 – 5.10||15||4.72||5.66||1.49|
|5.10 – 6.00||13||5.36||4.44||1.35|
Again we see that the Twins outperform against the tougher pitchers while not hitting the struggling pitchers as hard as one might predict. Overall, FIP seems to be a better indicator of future success against the Twins than ERA (shown in the table below):
|Surrounding ERA||Starts||Avg. ERA||R/9 v. Twins||WHIP v. Twins|
|3.00 – 4.40||16||3.76||3.71||1.21|
|4.40 – 5.25||10||4.84||3.44||1.24|
|5.25 – 6.50||10||5.74||6.54||1.61|
The first thing that jumps out is that the Twins are killing pitchers with an ERA under 3.00, so that backs up one part of the hypothesis. Although, taking these numbers with those of the previous table, it may be that the pitchers with the low ERA who have benefited from fielding help (and thus have a higher FIP) may be regressing to the mean a bit and inflating the numbers in the first row of this table. Also, the pitchers with the highest ERA outperformed their previous track record against the Twins, so there may be something to the perception after all. Note that the WHIP for the 6.50+ ERA category is lower than that of the below 3.00 ERA. However, the average pitchers (ERA from 3.00-5.25) seem to give the Twins the most trouble.
Overall, it seems that the data backs up the idea that the Twins struggle more than they should against pitchers who haven’t been having success. On the converse side, they don’t seem to be struggling with the most successful pitchers. It’s certainly an odd quirk, and I don’t know if it would hold up over a larger sample size, but it’s certainly interesting to see some numbers to back up my perception.
I’ll try to keep the database up to date and check in periodically with updates throughout the year. So you’ve got that to look forward to.