Two Months Later, Roberto Hernandez Still Getting It Done
At the end of May, I took stock of starter Roberto Hernandez‘s performance. He had, to that point, compiled a 3.76 ERA over 12 starts. In the four starts after that, he struggled, ballooning his ERA to 4.52, but he was the least of the Phillies’ concerns at the time.
Since then, in his last seven starts, Hernandez has notched five quality starts (missing a sixth by one-third of an inning) with a 2.85 ERA, lowering his overall ERA on the season to 3.87, only a smidge higher than it was the last time we checked up on the right-hander.
In March, we learned via GM Ruben Amaro that the Phillies’ new analytics department was responsible for bringing Hernandez to Philadelphia. Amaro didn’t go into any great detail about the specific reasons why they thought he would turn things around. However, Amaro did mention his home run rate. Pitchers, over a large sample of innings (several seasons’ worth), tend to regress towards the 10-12 percent league average on fly balls.
Hernandez allowed home runs on 21 percent of fly balls in 2013 with the Rays. Combining expected regression in that regard along with his improved strikeout rate (2013’s 17.6 percent strikeout rate marked a career-high), Hernandez was an easy buy-low target.
For the most part, the analytics department called it correctly on Hernandez. There have been two concerning factors which have led to some of Hernandez’s problems this season, however: his strikeout rate has declined to previous rates (14 percent) and his walk rate has ballooned to 10.4 percent, by far his highest rate over the last five years. His strikeout-to-walk ratio of 1.36 is his lowest out of any of his last five full seasons (20-plus starts).
Additionally, Hernandez has benefited from a .256 batting average on balls in play. It’s actually astonishing, considering the poor quality of the Phillies’ infield defense at the corners combined with Hernandez’s propensity to induce ground balls. It won’t last, of course. Hernandez’s xFIP is nearly a full run higher in 2014 than it was last year, 4.58 to 3.60. As the smart money was on Hernandez being better this year, the smart money is on Hernandez being worse going forward.
Baby steps. The Phillies were one of the last of the 30 teams in baseball to create an analytics department of some kind, and hopefully they have been enthused by the suave identification of Hernandez as a bounce-back candidate, and use it to make future personnel decisions. With Kyle Kendrick and Hernandez heading into free agency, with the potential to trade A.J. Burnett in the off-season (or this month), and with Cliff Lee‘s future in question, the Phillies will have to overhaul the starting rotation. They already have $128 million locked up for 2015, so they’ll need some savvy to round out the roster before next April.