The season is still very young, but that doesn't mean we can't crunch some peripheral numbers to see how the Yankees are doing and what to expect going forward. Here's a look at some standard and advanced metrics summarizing the Yankees production through 4/25/2014 with those same metrics from last year given as a reference. (All data courtesy of Fangraphs)
As expected, the offense has significantly improved compared to 2013. All three slash stats have gone way up and they're creating runs at an above average level. While the walk rate is still too close for comfort to last year's, it should improve as Carlos Beltran and Brian McCann get more acclimated to American League pitching. They're both currently walking at about half their career rate. Base running has also been a key to the offense's overall improvement. Last year's patchwork squad was about two runs below average, but Jacoby Ellsbury and company have already been two runs above average on the base paths and that will continue to rise. When putting the ball in play, luck has been on the Yankees side as they have hit .320. That will surely regress back towards .300 but will also be buoyed by a correction in home run rate. As the weather warms up, their HR/FB percentage should climb to 10% or higher and keep the run production steady. Barring catastrophic injuries, the offense should remain above average going forward.
Despite lights out performances by Masahiro Tanaka and Michael Pineda (the Pine Tar Kid) the Yankee arms have been only average so far. The bad news is that things will only get tougher as Ivan Nova's season ending injury will put Vidal Nuno and/or David Phelps in rotation and weaken the bullpen just a bit. The good news is that the peripheral numbers indicate an improvement is on the horizon. The team strike out rate is much higher than it was last year while their walk rate has remained steady, but home runs have been flying out of the park at an unsustainable rate. That means that if the home run rate regresses back to normal, as it should, the team ERA should steadily shrink as well, as evidenced by their FIP (which approximates ERA using only strike out, walk and actual home run rates) and xFIP (which approximates ERA using only strike out, walk and normalized home run rates). Couple that with the return of a healthy David Robertson and the Yankees' pitchers should perform at least as well as last year's solid staff did for the balance of the year.
Advanced fielding metrics can fluctuate wildly when taken in small sample sizes, but so far both standard and fancy numbers agree that the Yankees have been below average in the field. That idea is also substantiated by the difference in the pitching staff's ERA and FIP noted above. The real question, then, is whether or not to expect these wildly fluctuating metrics to positively regress as the season wears on. In order to answer that, let's look at the main culprit for the poor defense so far. According to the UZR components above, it's been a lack of range that has cost the team the most runs so far and, surprisingly, the numbers say that Jacoby Ellsbury is the worst offender at more than three range runs below average. Over the past three seasons, the same rating system has said that Ellsbury has actually saved about 12 runs per year thanks to his range alone. Therefore, unless he has completely forgotten how to field, it's expected that the advanced metrics will put Ellsbury, and the team as a whole, back in the black sooner than later.