There was little question about just how good the Yankees' outfield defense could be after the previous offseason. Jacoby Ellsbury and Brett Gardner are two of the best defensive outfielders in baseball, and although Alfonso Soriano has a bad reputation in the corner, his range over the last few years has gone from passable to above average. With Gardner headed back to left field, Soriano and Ichiro Suzuki switched to the smaller right field, and Ellsbury in center, the Yankees should have elite defense in the outfield. The bigger question surrounded the infield defense, which has been a major topic of discussion since the beginning of the season.
Starting 2014, the Yankees' pitching staff looked extremely ground ball friendly. Ivan Nova, CC Sabathia, Hiroki Kuroda, and Masahiro Tanaka each throw a heavy sinker to induce soft ground balls, and Michael Pineda was the only fly ball pitcher in the rotation. Since then, the Yankees have also brought Chase Whitley, David Phelps, and Vidal Nuno into the mix, and each of these three feature two-seamers and sinkers. But despite all of these sinker-heavy repertoires, the Yankees' rotation currently ranks 18th in baseball in ground ball rates, inducing ground balls at just a 44.5% clip. Contrary to what we expected this season, the Yankee rotation is very average in any rates of batted balls.
What the rotation is not average in, is their batting average on these batted balls. As it stands, the starting staff owns a .313 BABIP overall, which is the sixth highest in all of baseball. This high average on balls in play indicates three things, hard contact, bad defense, and luck. In the sample size of 4,616 pitches, luck plays a much smaller part in this high number, making hard contact and bad defense the two biggest factors in their poor BABIP. Hard contact may play a part, but pitchers with high strikeout rates generally tend to induce weaker contact. The Yankees' rotation ranks 10th in baseball in K%, and when you remove the National League teams, who have the pitching spot to strike out, the Yankees rank fourth in the American League. Contact can also be a factor when it comes to home runs, as a high home run rate can obviously lead to a higher batting average on balls in play. For the Yankees, who play in a hitter friendly park and league, the overall home runs per fly ball is actually relatively low at 9.3%, which ranks 22nd in all of baseball.
When it comes to more specific batted ball types, the Yankees' pitchers find themselves among the highest batting averages against. The team currently rank sixth in baseball on line drives (.708 batting average), third on fly balls (.199 batting average), and eighth on ground balls. The high batting average on ground balls is to be expected, as the state of the infield defense is abysmal. With Derek Jeter and Brian Roberts in their upper-30's, the range of the Yankees middle infield is extremely questionable. The Yankees' shifts don't seem like they're enough to counter the age and inexperience of this teams infield, and with that, Yankee pitchers have given up more hits than they should on ground balls. But overall, the number is much lower than I expected, as the Yankees have only allowed around eight more ground ball hits than your average team.
Surprisingly, there is a much bigger problem with the fly balls. As I mentioned above, the Yankees' pitchers have the second highest batting average against them on fly balls at .199. This means they've given up about ten more hits than your average team. While this again doesn't seem like a lot over a fifty game span, these hits are not bloops, as the Yankees are currently tied with the third most home runs against, seventh most doubles against, and second most triples. While a high home run rate is normal for Yankee Stadium, the park is actually extremely low in extra base hits because so many of them leave the park. This becomes a further problem when you see that the abnormally high extra base hits aren't isolated to a few pitchers. Sabathia owns the highest rate, but Kuroda, Nova, Nuno, Alfredo Aceves, and Pineda are all within 0.3% of each other following Sabathia.
And for as flawed as I believe advanced defensive statistics are, especially in such a small sample size, they generally all agree that the Yankees' outfield has been average to below average. At the moment, Jacoby Ellsbury owns a -18.2 UZR?150 and a -4 DRS, Soriano has a -8.7 UZR?150 and -5 DRS, Carlos Beltran a -22.9 UZR/150 with a -1 DRS, and Ichiro and Gardner are the only two outfielders with positive numbers. This isn't to say that Ellsbury and Soriano actually have atrocious range, but seeing as the Yankees have allowed so many more fly ball hits than your average team, it's at least understandable why the statistics dislike the Yankees' outfield.
So with all the talent the Yankees have between Ellsbury, Gardner, Soriano, and Ichiro, why are they allowing so many fly balls and extra base hits? It's possible that the Yankees pitching has just been bad, but as I mentioned, the high strikeout rates of this pitching staff should correlate with weaker contact. The amount of extra base hits aren't isolated to a few bad pitchers either, but it's well spread out across the roster. Though it's tough to prove causation, there's a chance that the Yankees' outfield shifts are one major factor in allowing so many costly fly ball hits.