This article will be updated periodically, as the playoff-specific PECOTA lines are processed for the matchups. Stay tuned throughout the day for updates.

The playoffs are here, folks, with three of the Division Series set to kick off throughout the afternoon and evening. First, the Rays and David Price take on the Rangers and Cliff Lee. As that game draws to a close, post-season newcomers Roy Halladay and Edinson Volquez headline the Phillies-Reds series. And for the nightcap, CC Sabathia looks to put the Yankees ahead against Francisco Liriano and the Twins. Earlier this week, several of my colleagues did an exemplary job breaking down each component of every series, but today, and throughout the postseason, I am going to discuss how PECOTA thinks the players involved will perform, based on the specific rotations for each series.

It isn’t exactly breaking news that Colin Wyers has been breaking down doors and taking names with regards to the PECOTA process and one of his innovations is applying the projections to the playoffs. While I don’t want to get too bogged down in the details, the process works very much in the same way as the simulations of which I have written about in the past, in which the results are contingent upon the specific matchup between the batter and pitcher. After all, seasonal lines are comprised of numbers produced against a motley crew of pitcher archetypes, whereas in the playoffs batters will be facing the best of the best.

Essentially, PECOTA is used to generate expected rates of each event for a batter and a pitcher, playing at a neutral site. Then we compare those expected component rates using the Odds Ratio to come up with a specific line for each batter against each pitcher, given the respective quality of each. The expected lines are then adjusted to account for the specific park and the effects of home field advantage on the individual components. These projected lines are then combined to form an expected batting line for each lineup and converted into runs using linear weights. Again, these aren’t what we would expect these batters to do in the regular season, but rather what they are going to be expected to do against the top of a rotation and top-notch relievers.

The reason using PECOTA forecasts as a proxy for playoff performance is more accurate is that it is too often overlooked that regular-season numbers do not represent true talent levels. Josh Hamilton may have played out of his mind this season, but it would be foolhardy to simply expect the same version of him to show up in the playoffs. Maybe he will continue to knock the cover off of the ball, but if one were to bet, the safest wager would be placed on an estimation of his true talent level. So if some of the numbers look off to you, please don’t yell or call me names. These numbers are in no way 100 percent accurate, but the underlying methodology is sound and it is a much more accurate exercise to base results off the true talent of the players involved.

Rays vs. Rangers

PECOTA Game One Prediction: Rays 54% to Rangers 46%

First up, we have the Rays and Rangers, who have the honor of officially starting the 2010 postseason. As was mentioned at the top, the pitching matchup is between Price and Lee. Below you will find how the expected lineups are projected to perform against each pitcher. Keep in mind that it is probably more telling to show the projected slash lines as opposed to anything else, and for now we will stick with the starting pitchers. From a run scoring standpoint, the Rays are projected to score 3.85 runs to the 3.52 runs of the Rangers.


Rangers vs. David Price






Elvis Andrus




Michael Young




Josh Hamilton




Vladimir Guerrero




Nelson Cruz




Ian Kinsler




Jeff Francoeur




Jorge Cantu




Bengie Molina





Rays vs. Cliff Lee






B.J. Upton




Jason Bartlett




Carl Crawford




Evan Longoria




Ben Zobrist




Dan Johnson




Kelly Shoppach




Carlos Pena




Sean Rodriguez





Simply put, PECOTA expects the Rays to have an easier time against Lee than the Rangers will against Price. Though Hamilton is the only lefty in the lineup that will suffer from a platoon split, he is still expected to perform extremely well relative to his colleagues. What hurts the Rangers here is the bottom of their order as well as being on the road. While Francoeur, Cantu, and Molina could easily surpass their projections given that a southpaw is on the mound, none of the three is particularly adept at swinging the bat, which will be magnified against the best starting pitchers a team can offer.

The Rays get the home field benefit, which helps a lot given that Tropicana Field is considered the fifth hitter-friendliest park in the majors per the park factors used in the calculations. If these numbers are any indication of what is to come, then the key for the Rays will be Carl Crawford, who projects to be the top hitter in the game. The Rays are likely to finagle their lineup given the handedness of the opposing pitcher, so these numbers will change between as the series goes on, but as it currently stands they have a big advantage in this matchup. Keep in mind, however, that over one game that advantage is only translating to 0.35 runs, so while the Rays should win this game on paper, would it really surprise anyone to see Lee completely shut down his opponent?

If or when the starters are removed from the game and this becomes a battle of the bullpens, the Rays should hand the ball to Joaquin Benoit and Rafael Soriano. That tandem provides the best chance at shutting down the big boppers of the Rangers. Lance Cormier looks like he could be capable of shutting down the likes of Andrus, Francoeur, Cantu, and Molina, but he should not be brought into face Kinsler, Guerrero, or Hamilton. Kinsler has a projected .286/.357/.478 line off of Cormier; Guerrero is at .303/.350/.497; and Hamilton chimes in at .297/.357/.509.

For the Rangers, Darren O’Day actually provides the best chance of shutting down any of the Rays hitters, though for some the difference between he, Darren Oliver, and Neftali Feliz is marginal at most. Against Upton, the three relievers are equally effective, though with so many lefties in the lineup, it quickly becomes evident that Oliver has a much more substantial advantage against the opposition than O’Day or Feliz. Lee has pitched deep into almost every game he has started this season, so unless the Rays tee off on his offerings, Ron Washington should be able to utilize his lefty specialist to his fullest late in the game.

This will be needed to overcome the difference in projected runs scored. In the end, PECOTA thinks the Rays will win, though a 54 percent shot isn’t by any means a lock.

UPDATE, 4:44 Central: This is Colin, filling in for Eric as your ringmaster here. This is not so much a projection as just a jection, but better late than never, I should think. This is pretty much the same thing as above, except for I had to come up with a projected line for the ninth spot in each lineup that accounted for pitcher hitter and pinch hitting. I've kept that generic – same for both teams.

This will not shock anyone, but PECOTA sees Roy Halladay as very, very good at pitching, and Edinson Volquez as… not as good as Roy Halladay. The Reds are expected to score 3.94 runs, compared to 5.46 for the Phillies. Using Pythagenpat, that comes out to a 35% shot for the Redlegs, compared to a 65% shot for the Phillies.

Expect updates in a little while, as I get the Yanks-Twins lineups ready to go.

UPDATE 8:24 P.M. Eastern: The Seidmeister is back after almost being brought to tears by the performance of Roy Halladay to update everyone on the upcoming Twins-Yankees matchup. So, what does PECOTA think will happen in the first game?

The Yankees are in Minnesota, with CC Sabathia facing Francisco Liriano. According to PECOTA, the two southpaws are virtually dead even, regardless of any type of qualitative aura surrounding Sabathia. The differences between the teams then involve the lineups and the relief corps. The Twins have a disadvantage in the fact that their two best hitters — Joe Mauer and Jim Thome — swing from the side of the plate most advantageous to Sabathia, a problem that doesn't plague the Yankees in their battle with Liriano. The Twins do, however, have the home field advantage working for them, and even after adjusting for the likelihood that Mariano Rivera logs the lion's share of bullpen inning and debiting Mauer and Thome a bit more to be conservative, the Twinkies still come out ahead. PECOTA foresees the Twins scoring 4.6 runs to the 4.16 of the Yankees, which would give the supposed underdogs a 53% chance of winning.

Now, that might seem strange to some, but remember that a 53/47 split is minuscule and is essentially equivalent to a coin-flip. On paper, the Yankees are the better team, but home field advantages in performance should not be underrated. The fact that Sabathia could neutralize the Twins' best hitters may come into play more than we are expecting, and Liriano could turn in a poor performance, but then why should we have to explain why the Twins are projected to beat the Yankees in this first game? It isn't as if the Twins were akin to the 2006 Cardinals, making the playoffs by the skins of their teeth. The Yankees are probably predicted to win the series by 100% of predicting analysts, but these two teams appear to be more evenly matched than meets the eye, at least in this first game.

Thank you for reading

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Looks like PECOTA spit out what ended up being Pinnacle's no-vig closing line. Good work.
Colin, what fraction of the hitter's line is from the pitcher/defense component?


The way this works is that the batter has a projected rate in an event, and so does the pitcher. Maybe Halladay has a projected rate of getting outs of 67.2 percent of the time, and Jay Bruce has a projected rate of making outs at 62.4 percent of the time. Using the Odds Ratio formula which I described in my article here "Pujols and the Simulation Gauntlett" the combination of those two would give Bruce a 64.6 percent shot of actually being out. Even though his overall rate is lower, the fact that he's facing a tougher pitcher makes it increase. So that is repeated for all of the events.
Are platoon splits included in this?
These are great, Eric. Are you planning on keeping them up for every game?
Yeah, the only thing we need to do is refine the process. Colin, John and I pretty much worked 24 hours on these but now we have it down pat, so each day we'll have the projected lineups, the slash lines, the odds of each team, and blurbs from Colin and I on what we're seeing in the data.
This is awesome! Thanks for the good work, Colin, John, and Eric. Nice to see this on a game-by-game basis.
Pretty neat work. Also a nice way to pick up things to look for before the games start.
Doc Halladay scoffs at 3.94 expected runs. :)