Stats Corner: Did Pirates win Grilli-Frieri trade?
The Pirates and Angels exchanged scuffling former closers recently, with the Bucs sending Jason Grilli to L.A. for Ernesto Frieri. At first blush, shipping 2013 All-Star Grilli away for Frieri — who had the highest ERA (7.29) among qualified relievers in 2014 — looks dubious. But the 28-year-old, fastball-centric right-hander still possesses the skills that allowed him to convert more saves (37) than Grilli (33) a year ago.
Frieri is striking out plenty of batters (10.5 strikeouts per nine innings) and limiting walks (a career-low 2.4 BB/9). Yet his ERA has spiked because of terrible luck on balls put in play and a few wall-scraping home runs. Frieri's BABIP this season is .367, 90 points above his career average (.277). About one of every five fly balls hit against Frieri is leaving the yard — double his career average.
BABIP and home-run-per-fly-ball numbers tend to regress toward a pitcher's career mark over time, so Frieri shouldn't surrender as many bloop hits and just-enough blasts in the second half. With better luck, Frieri should start preventing runs at the dominant clip his strikeout and walk totals suggest.
He actually is turning in his finest major league season, according to expected Fielding Independent Pitching (xFIP), an ERA estimator based on strikeouts, walks and a normalized home run per fly ball ratio. Frieri has the largest gap between his ERA and xFIP among qualified relievers.
Pitcher xFIP ERA Diff.
Ernesto Frieri 3.28 7.29 -4.01
Josh Fields 2.83 5.65 -2.82
Nick Vincent 3.24 5.67 -2.43
Joe Nathan 3.94 6.16 -2.22
Edward Mujica 3.57 5.76 -2.19
Grilli, by contrast, is striking out fewer hitters and issuing more walks, leading to a 4.42 xFIP that's a near match for his actual 4.18 ERA. Considering Frieri's youth and contract status (he's under team control through 2016), this challenge trade looks like a winner for the Pirates.