What to Think of Zach Eflin

I don’t know about you, but I hadn’t really heard of the Phillies fifth-starter-turned-surprising-best-pitcher (by recent results, not actual skills) much before this year. He was drafted by the Padres in 2012, never got higher than #9 in their organizational prospect lists, was traded to the Dodgers in the Matt Kemp deal, and then sent to Philly for Jimmy Rollins. He was always considered to have a low ceiling, but a likely high floor. That’s really a good trait for a back-end starter or long-reliever.

After some key injuries to the Phillies rotation this season, Eflin was called up in June. He’s made eight starts in the majors, after putting up a 2.9 ERA and 2.52 FIP in AAA. He got rocked by the Blue Jays in his first start (the Rogers Centre is a terrible place to debut), giving up 8 earned runs in 2.2 innings. Since that start, here are his stats:

That ERA is pretty. The FIP is also good. How ‘bout that crazy walk rate? That is the third best rate in baseball this season, behind only some guy named Kershaw and Josh Tomlin. And look! His strand rate is near league average, so he hasn’t been lucky by stranding a bunch of runners.

What’s that? Oh, there’s other stuff in that table too. You know, like his 13.2% strikeout rate (11th worst in baseball), terrible xFIP and SIERA, very low (lucky?) BABIP, and his low HR/FB rate (which actually jumps up to a reasonable 9% if you include his Toronto disaster). His swinging strike rate of 6.6% fully justifies the terrible strikeout rate.

Look, I could just say he’s been very lucky and that he will quickly regress to his xFIP and SIERA and become a useless pitcher for fantasy purposes. But that’s a lazy analysis and far too easy. He’s kept this up for 47+ innings now and just threw a shutout against the Pirates. So, how is he doing this?

The first guess might be that he is an extreme ground ball pitcher, but that’s wrong. He’s got a measly 38% GB%. His two most used pitches (four seam and slider) both are thrown to get fly balls (29% and 35% ground ball rates). His two seam fastball and changeup both get 50+% grounders, but they just don’t have the volume to drive up his overall rate.

Guess #2: he gets lots of pop-ups, which are just like strikeouts since they are nearly automatic outs. His 10.4% IFFB% puts him at #72 in baseball, which is just average. Nothing to see here.

Guess #3: he’s limiting hard contact. Guys like Bumgarner, Kershaw, and Hendricks are very good at this. They can prevent the hitter from making solid contact, resulting in low exit velocities and hard hit %. In hard hit%, he is #68, again average. His average exit velocity is also right in the middle of the pack at 89.3 mph, with the leaders down below 86 mph. Wrong again.

Guess #4: He keeps hitters off balance by working from ahead in the count. His first strike % of 64.5% is 30th best in baseball (all stats are for pitchers with 50+ innings). We’re off to a good start. Using Baseball Savant’s excellent search feature, I found that Eflin has pitched ahead in the count about 49% of the time, good for 80th best among pitchers with more than 500 pitches thrown. That is out of 326 pitchers, so he’s definitely in the upper tier, but he really needs to be elite at this to justify his excellent results. This might be part of his success, though.

Guess #5: He pounds the strike zone, but hitters don’t swing as much as you would expect, especially since they make lots of contact against him. His Zone % is #9 in baseball at 50%. His zone contact % is #20 at 91.5%. However, hitters are only swinging at 67.4% of his in-zone pitches, 58th from the top. He’s 99th in % of pitches that are called strikes, and when you add in foul balls, he falls to #153. So, he’s not really getting a ton of called strikes and not getting too many foul balls. Hitters are making contact at an average exit velocity and making contact a lot, given all the strikes Eflin is throwing.

Guess #6: I think this is the big one. I’ve looked everywhere by now trying to find something and I think this is it. In spite of 4 HR and a slightly higher wOBA allowed to lefties (0.297 vs 0.282), he is extremely lucky lefties haven’t demolished him yet. Here is his line against LHB:

Wow that is ugly. He is so fortunate that he’s only allowed a 0.233/0.274/0.433 line to lefties so far. Look at that 0.213 BABIP. When that comes crashing back to earth (and it will), he’s going to have some trouble. How soon will that happen? I don’t know. With all the contact he allows, especially to lefties, it’s only a matter of time before he gets rocked again. Against righties, he has a very good 15.7% K%-BB%, and 3.06 FIP. Unfortunately, his change-up isn’t very good and he doesn’t use it much, so he can’t use a pitch designed to get opposite-handed hitters out.

Until he develops a better off-speed pitch with arm-side break, he’s going to have some really rough times ahead against lineups with lots of lefties. I own him in a very deep league and I’m riding his current streak, but I’m ready to let go at any time because a string of starts like his Toronto one could come soon.

In the end, it did come down mostly to luck, particularly against lefties. His “pound the strike zone” approach proves his tiny walk rate is real, but just ask Phil Hughes how that approach can easily backfire. He forces hitters to swing by throwing strikes, but eventually he will need to either generate more strikeouts, reduce exit velocities, or generate more pop-ups to avoid ending the year with an ERA in the mid-4s. Your move, Eflin.

A quick shout-out: Daniel Kelley, a fellow Fake Teams writer, has successfully convinced a publisher that he can write and has created a book! An entire, 374-page book with words and stuff! You can buy it over at that rainforest site (you know, Amazon), if you enjoy creative original takes on the zombie apocalypse theme. Tschus!