The Pittsburgh Pirates Aren’t Regressing

At the end of May, I wrote a post noting that it was time to take the Pittsburgh Pirates seriously. At that point, they were 33-20, and I spent the first few paragraphs of the piece explaining why the Pirates were probably playing over their heads and were due for some regression. After all, the Pirates weren’t going to keep winning games at a .622 pace. They were interesting, but they weren’t that good.

Well, on the one hand, the prediction of coming regression has been correct. After going 33-20 in their first 53 games, they’ve gone 32-22 in the 54 since that piece was published. 32-22 is worse than 33-20. They’ve regressed, technically.

On the other hand, we could actually say that the Pirates have gotten even better.

In that piece, I produced a table of each team’s wOBA differential, and noted that the Pirates 18 point advantage over their opponents suggested that their record wasn’t all luck. They had the same wOBA differential at that point as teams like the Braves, Rays, and A’s, and so while a .622 clip couldn’t be expected, they were playing like a team that should stay in a playoff race for the entire year.

Well, here’s that same table, updated through yesterday’s games. Run differential is on a per game basis, by the way.

Team wOBA (Offense) wOBA (Defense) wOBA Differential Run Differential Winning %
Tigers 0.343 0.298 0.045 1.25 0.576
Rays 0.328 0.297 0.031 0.64 0.593
Braves 0.324 0.298 0.026 0.94 0.583
Cardinals 0.322 0.297 0.025 1.12 0.585
Red Sox 0.340 0.319 0.021 0.89 0.596
Pirates 0.307 0.286 0.021 0.60 0.608
Reds 0.316 0.297 0.019 0.76 0.551
Athletics 0.314 0.296 0.018 0.59 0.583
Dodgers 0.316 0.301 0.015 0.07 0.538
Rangers 0.322 0.308 0.014 0.12 0.546
Indians 0.328 0.316 0.012 0.48 0.551
Angels 0.325 0.324 0.001 -0.19 0.453
Orioles 0.327 0.327 0.000 0.19 0.546
Cubs 0.308 0.309 -0.001 -0.18 0.458
Rockies 0.324 0.326 -0.002 -0.12 0.468
Diamondbacks 0.311 0.314 -0.003 0.16 0.514
Blue Jays 0.324 0.327 -0.003 -0.19 0.467
Brewers 0.312 0.317 -0.005 -0.59 0.426
Giants 0.305 0.311 -0.006 -0.56 0.443
Mariners 0.310 0.317 -0.007 -0.50 0.467
Nationals 0.299 0.308 -0.009 -0.34 0.482
Mets 0.301 0.310 -0.009 -0.30 0.457
Royals 0.301 0.313 -0.012 0.05 0.510
White Sox 0.297 0.312 -0.015 -0.73 0.381
Yankees 0.295 0.311 -0.016 -0.06 0.523
Phillies 0.307 0.326 -0.019 -0.76 0.467
Padres 0.303 0.324 -0.021 -0.52 0.459
Twins 0.306 0.332 -0.026 -0.52 0.433
Marlins 0.277 0.309 -0.032 -0.90 0.387
Astros 0.295 0.354 -0.059 -1.46 0.340

Two months ago, the Pirates +18 point wOBA differential ranked eighth best in baseball; today, their +21 point wOBA differential ties them with the Red Sox for the fifth best mark in the sport. Instead of regressing, they’ve almost perfectly maintained their early season performance. Their offensive wOBA went from .306 to .307 and their wOBA against — the part of their team that looked to be the most “flukey” — actually went down from .288 to .286. Basically, the Pirates have spent the last two months winning the exact same way they won the first two months: elite run prevention and a good enough offense.

In reality, the Pirates are just the National League version of the A’s, who are running away with the American League West based on success with the same formula. The A’s wOBA is a little higher (.314), but they play in the American League and have the benefit of the DH. If you excluded pitcher hitting and just focus on what a team has gotten from their position players, the Pirates .319 wOBA actually rates as the 15th best in baseball, especially impressive given that they play in a fairly extreme pitcher’s park. Park adjusted, their position players have combined for a 104 wRC+, ninth best in the game.

Like with the A’s, the offense is solidly average, maybe even a tick above, but it’s the run prevention that is carrying the day. The A’s rank second to the Pirates in opponents wOBA, coming in at .296, and again, the number is slightly higher but also comes in the DH league. In terms of overall difference, the Pirates have the A’s edged out 21 points to 18 points of wOBA, but in practical terms, both teams are winning the same way.

The comparison continues when we look at why both Pittsburgh and Oakland have been so successful at keeping opponents from scoring. Pittsburgh’s BABIP allowed is just .267, #1 in baseball. Right behind them are the A’s, at .270. Behind them are the Rays, at .278.

What do all these teams have in common? A heavy focus on defensive value. The Pirates, A’s, and Rays have spent the last few years pursuing athletes who can both hit and cover ground in the field, and each of these teams has put multiple center fielders side by side in the outfield. In addition, the Pirates and Rays are two of the most aggressive shifting teams in the Majors; BIS posted updated shift totals for the top five teams last week, and the Pirates were #2 and the Rays were #4 in their shift usage.

Not surprisingly, these teams feature some of the most “surprising” pitching performances in the Majors this year. Bartolo Colon is amazing at age 40! Francisco Liriano is good again! A.J. Burnett is throwing like an ace! Where did Alex Cobb come from?!? Not to totally discount the quality of pitcher that these teams have collected, but sticking effective defenses behind decent pitchers has a tendency to make them look more than decent.

The Rays don’t fit quite as well as a comparison to the Pirates and A’s because their offense is better — their .328 wOBA ranks #3 in the majors — but they are built on a similar foundation. They’re the best of the teams in this mold, but the A’s and Pirates aren’t that far behind.

And yes, it is now time for the Pirates to be considered a serious threat in October. They might not have made any substantial upgrades at the deadline, and they still have a number of players performing over their heads, but this is a good baseball team, and one that has a relatively smooth path to postseason baseball.

With their surge and the Cardinals recent slump, Cool Standings now estimates that the Pirates have a 52% chance to win the division, and even if they don’t hang on to the NL Central title, they are extremely likely to snag one of the two wild card spots, earning a spot in the play-in game in 97.2% of the trials in which they didn’t win the division. They have a 10 game lead over the Arizona Diamondbacks, who currently hold the sixth best record in the NL. Teams have blown 10 game leads two month stretches before, but it’s not easy, and because the season started earlier and ends earlier this year, we’re actually a bit further into the season on August 1st than we are in most other years.

For the Diamondbacks to pass the Pirates and capture the final wild card spot, Arizona would have to outplay Pittsburgh by 200 points of winning percentage, which is about the difference between the Braves and Marlins thus far. If you expect the Pirates to begin to play like the worst team in baseball starting today, then the D’Backs just need to play like the best team in baseball in order to run them down.

Unlikely is being kind. The Pirates haven’t completely locked up a spot in the postseason yet, but they’re close to doing so. It would take a pretty epic collapse for their season to end on Game 162. Their fight now is to try and win the NL Central, because their performance in the first four months of the season has given them a significant cushion in the race for a wild card spot.

It’s time to stop expecting the Pirates to collapse. Their offense is solid, their pitching is pretty good, and their defense is terrific. This formula works.

Dave is the Managing Editor of FanGraphs.

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10 years ago

I haven’t looked at the offense at all, so that’s really interesting. I did dive a little into the pitching side of things, and while I haven’t looked since the start of the second half, the Pirates are doing this with a great ground ball rate, low BABIP (agree probably related to their excellent defense*) and very high strand rate. As for BABIP, between 2009 and 2012, only the ‘11 Rays had a BABIP below .270, and only two other teams had a BABIP below .275 (full season). And that LOB% was two standard deviations beyond the mean (if I did my math right), so not sure that can continue either. Anyway, more here:

*I also believe this is why the Tigers BABIP is so high and was unlikely to regress until Tuesday’s trade. I’m much higher on the Tigers today than I was on Monday.

10 years ago
Reply to  Otter

Just about every single babip fluctuation we see over a season can, yeah, probably be attributed to great defense and ground ball pitching. The only thing that concerns me about this year’s Pirates is the high strand rate, but Hisashi Iwakuma doesn’t seem to have a huge problem with his LOB% in Seattle. Is strand rate really a matter of luck, in the same way that the Cards seem to be really lucky with guys in scoring position? Or is Iwakuma, for example, just above average when the pressure’s on? Peripheral stats can’t account for these things.

Climbing The Wall
10 years ago
Reply to  frivoflava29

I’m not sure how “lucky” LOB% is. I think there’s a decent correlation between K% and LOB%. Just my opinion, but I consider BABIP to be more “lucky” than LOB%.

Spencer D
10 years ago

You might throw substantially harder with two guys on, than with 2 out nobody on, I would think.