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The dejuiced playoff ball plays an awful lot like the juiced ball at Oracle Park

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Almost immediately, baseball fans noticed that the ball was carrying differently in the postseason, but everything looked normal to Giants fans.

New York Mets v. San Francisco Giants Photo by Daniel Shirey/MLB Photos via Getty Images

Arguably, the biggest story line to come out of the postseason has been the apparent change in the ball. Over at Baseball Prospectus, Rob Arthur showed that the postseason baseball has significantly more drag which is causing it to not travel as far. As of October 10, Arthur calculated that there have been 50 percent less homers than we would expect in the regular season. It’s not just Arthur either, the St. Louis Cardinals analytics team also found that the ball is traveling around 4.5 feet less on average. Players, fans, broadcasters, and cameramen have been getting fooled by would-be homers. The Dodgers celebrated what might have been a walk-off just to see Will Smith’s liner flop harder than Will Smith’s Gemini Man. Ronald Acuña Jr. was criticized for admiring a ball that was a homer in the last game he played. Baseball fans have had a hard time adjusting to how the new ball travels, but for Giants fans, watching this ball doesn’t feel any different.

Oracle Park is the most difficult ballpark in which to homer. A few years ago, Grant wrote about how the home run surge passed Oracle Park by, and earlier this year, Eno Sarris and Andrew Baggarly wrote about how the stadiums low temperature, low elevation, and extreme dimensions turn homers into outs. In a year where Paul DeJong and his 100 wRC+ can hit 30 bombs, the Giants were overjoyed to even get one stinkin’ 20-homer hitter and delirious with dingerlust to get three.

While everyone has been talking about the postseason dejuiced ball and the lack of homers, I’ve been thinking that the rest of the baseball universe finally knows what it’s like to watch baseball at Oracle Park. Only now do they get to know the frustration of watching their players do the best possible thing only to have the ball caught.

Using data from Baseball Savant, I looked at the percentages of fly balls that have gone over the fence in the regular season, in the playoffs, and at Oracle Park. For the balls hit at Oracle Park, I included those hit by the visiting team so it’s not just the Giants’ feckless offense dragging the numbers down. I did the same for barrels. What I found is that Oracle Park had the lowest percentage of fly balls and barrels turn into homers by a wide margin.

Fly Ball and Barrel Results

Season/Venue Flyballs Home Runs HR/FB Barrels Barreled Homers HR/Barrels
Season/Venue Flyballs Home Runs HR/FB Barrels Barreled Homers HR/Barrels
Regular 29868 5958 19.95% 9290 5536 59.59%
Post 348 60 17.24% 124 62 50.00%
Oracle 1027 147 14.31% 295 133 45.08%
Reg - Oracle 28841 5811 20.15% 8995 5403 60.07%

At every other park in the majors, barrels turned into home runs 60 percent of the time. In the postseason, that dropped ten percentage points. That’s a massive difference, but not so big to compared to drop-off to Oracle Park where only 45 percent of barrels left the yard. Fly balls hit during the regular season had a 20 percent of turning into a dinger. In the postseason, that’s down to 17 percent, but at Oracle, only 14 percent of flies went over the fence.

Now, not all fly balls are created equal. Looking at xwOBA versus actual wOBA, the postseason ball has had slightly worse results than the juiced ball at Oracle and both have substantially worse results than the regular season.

Expected Results

Season FB wOBA-xwOBA Barrel wOBA-xwOBA
Season FB wOBA-xwOBA Barrel wOBA-xwOBA
Reg 0.053 0.092
Post -0.034 -0.110
Oracle -0.016 -0.088

If this ball is the new normal, the Giants will never hit a home run at Oracle Park again. Unless, of course, the fences are brought in. We’re still waiting to see what the Giants will do with the bullpens. The obvious solution would be to put them in Triples Alley, but they also might explore a solution similar to the one employed at Wrigley where the bullpens are placed underneath the bleachers. Regardless, we have another week or two of games with the juice dial set to Oracle.