Poll 2024: Which Group of Pitchers Performs Better?
Yesterday, I asked you to vote on which group of hitters you expect to post a better wOBA over the rest of the season. One group was composed of the 10 biggest xwOBA overperformers, while the other comprised the underperformers. Let’s now shift over to starting pitchers by comparing ERA to SIERA, pitting the SIERA overperformers against the underperformers during the pre-all-star break period. This is the poll I began with back in 2013.
I came up with this idea given my faith in using SIERA over smaller samples, rather than ERA, as I generally ignore ERA completely as late as the middle of the season and it’s interesting to see how everyone else thinks. Will the SIERA overperformers continue to outperform, perhaps due to continued strong defensive support and/or more pitcher friendly ballparks, or will the magic disappear? Is it just bad luck that is due to reverse course for the SIERA underperformers or are they being hampered by one of the aforementioned factors that should continue to play a role the rest of the way?
My initial population group consisted of 118 pitchers who have thrown at least 70 innings. Group A is composed of the 10 largest SIERA overperformers, while Group B is composed of the 10 largest SIERA underperformers. Let’s compare.
| Name | LD% | GB% | FB% | IFFB% | HR/FB | BABIP | LOB% | K% | BB% | ERA | SIERA | Diff |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Tyler Anderson | 18.9% | 36.6% | 44.6% | 12.2% | 9.0% | 0.228 | 83.2% | 16.8% | 9.8% | 2.97 | 5.09 | -2.12 |
| Reynaldo López | 22.7% | 38.0% | 39.2% | 10.0% | 6.0% | 0.287 | 86.9% | 24.6% | 8.8% | 1.88 | 3.96 | -2.08 |
| Albert Suárez 수아레즈 | 23.8% | 33.3% | 42.9% | 10.0% | 4.4% | 0.276 | 79.4% | 18.5% | 8.4% | 2.82 | 4.67 | -1.85 |
| Ronel Blanco | 16.6% | 39.2% | 44.2% | 12.8% | 12.8% | 0.178 | 86.3% | 23.4% | 9.8% | 2.56 | 4.25 | -1.69 |
| Michael Lorenzen | 17.0% | 43.6% | 39.4% | 14.7% | 12.7% | 0.224 | 82.0% | 17.4% | 11.8% | 3.52 | 5.18 | -1.66 |
| Andrew Abbott | 17.3% | 33.5% | 49.2% | 11.7% | 11.7% | 0.238 | 84.9% | 19.4% | 9.0% | 3.39 | 4.75 | -1.37 |
| Marcus Stroman | 15.4% | 50.0% | 34.6% | 10.2% | 13.9% | 0.258 | 81.0% | 17.4% | 10.5% | 3.51 | 4.88 | -1.36 |
| Seth Lugo | 20.5% | 43.0% | 36.5% | 9.2% | 8.5% | 0.277 | 83.2% | 22.6% | 5.8% | 2.48 | 3.80 | -1.32 |
| James Paxton | 20.8% | 36.3% | 42.9% | 8.1% | 9.0% | 0.268 | 74.3% | 15.6% | 12.0% | 4.38 | 5.54 | -1.16 |
| Corbin Burnes | 16.8% | 49.4% | 33.8% | 14.2% | 11.5% | 0.265 | 82.2% | 23.3% | 5.3% | 2.43 | 3.55 | -1.13 |
| Group Average | 18.8% | 40.7% | 40.6% | 11.4% | 10.1% | 0.250 | 82.3% | 20.0% | 9.0% | 2.96 | 4.52 | -1.56 |
| League Average* | 19.9% | 41.8% | 38.3% | 10.2% | 11.8% | 0.289 | 72.3% | 21.8% | 7.6% | 4.13 | 4.11 | 0.02 |
| Name | LD% | GB% | FB% | IFFB% | HR/FB | BABIP | LOB% | K% | BB% | ERA | SIERA | Diff |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Kyle Hendricks | 22.7% | 44.2% | 33.0% | 15.6% | 16.9% | 0.326 | 60.1% | 16.3% | 6.8% | 6.78 | 4.52 | 2.26 |
| Pablo López | 20.4% | 39.6% | 40.0% | 11.4% | 15.8% | 0.305 | 65.5% | 27.9% | 5.3% | 5.11 | 3.20 | 1.90 |
| Brayan Bello | 23.9% | 51.5% | 24.6% | 9.0% | 20.9% | 0.328 | 69.3% | 21.4% | 8.3% | 5.32 | 3.95 | 1.37 |
| Spencer Arrighetti | 22.4% | 38.1% | 39.5% | 12.5% | 12.5% | 0.344 | 70.0% | 25.4% | 12.0% | 5.63 | 4.28 | 1.34 |
| Ryan Feltner | 19.7% | 46.4% | 33.9% | 10.2% | 11.1% | 0.333 | 58.4% | 20.3% | 7.3% | 5.36 | 4.17 | 1.20 |
| Logan Allen | 17.2% | 42.7% | 40.1% | 12.1% | 16.8% | 0.324 | 72.9% | 19.7% | 9.1% | 5.67 | 4.55 | 1.12 |
| Yusei Kikuchi | 20.3% | 40.9% | 38.9% | 9.4% | 13.7% | 0.331 | 72.9% | 26.0% | 5.8% | 4.42 | 3.45 | 0.97 |
| Chris Paddack | 21.5% | 37.3% | 41.2% | 9.6% | 12.2% | 0.327 | 70.9% | 20.6% | 5.5% | 4.99 | 4.08 | 0.91 |
| Dylan Cease | 18.5% | 34.5% | 46.9% | 7.8% | 11.6% | 0.275 | 68.6% | 31.9% | 7.7% | 3.99 | 3.09 | 0.90 |
| Aaron Civale | 24.5% | 33.7% | 41.8% | 9.8% | 15.4% | 0.308 | 74.1% | 22.8% | 7.5% | 4.94 | 4.06 | 0.89 |
| Group Average | 21.1% | 40.9% | 38.0% | 10.5% | 14.4% | 0.320 | 68.3% | 23.6% | 7.5% | 5.13 | 3.88 | 1.25 |
| League Average* | 19.9% | 41.8% | 38.3% | 10.2% | 11.8% | 0.289 | 72.3% | 21.8% | 7.6% | 4.13 | 4.11 | 0.02 |
| Group | LD% | GB% | FB% | IFFB% | HR/FB | BABIP | LOB% | K% | BB% | ERA | SIERA | Diff |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| A | 18.8% | 40.7% | 40.6% | 11.4% | 10.1% | 0.250 | 82.3% | 20.0% | 9.0% | 2.96 | 4.52 | -1.56 |
| B | 21.1% | 40.9% | 38.0% | 10.5% | 14.4% | 0.320 | 68.3% | 23.6% | 7.5% | 5.13 | 3.88 | 1.25 |
| League Average* | 19.9% | 41.8% | 38.3% | 10.2% | 11.8% | 0.289 | 72.3% | 21.8% | 7.6% | 4.13 | 4.11 | 0.02 |
What’s pretty incredible is that Group A (the overperformers) have posted an identical ERA so far as last year’s Group A. The SIERA is pretty close to, with this year’s group posting a mark just 0.09 runs higher. On the other hand, Group B (the underperformers) have both been significantly better than last year in terms of results (ERA), and in terms of underlying skills (SIERA). In fact, Group B’s skills are dramatically better than Group A’s this year, whereas last year they did post a worse SIERA.
The batted ball profiles of the two groups are fairly similar, but Group A has suppressed line drives, allowing more fly balls instead, while the group has also generated a slightly higher rate of pop-ups. That should result in a lower BABIP, but not by a significant margin. Moving along to the trio of “luck” metrics, we find the explanations behind the ERA discrepancies. Group A has posted a better than average HR/FB rate, while Group B can’t keep their fly balls allowed in the park. We see a massive difference in BABIP, and one that definitely isn’t explained by the small differences in batted ball type profile. Finally, Group A has stranded over 80% of baserunners, likely due to a combination of better relief support, as well as the aforementioned lower HR/FB rate and especially BABIP. Meanwhile, Group B is down below 70%, again, due to the inflated HR/FB rate and BABIP mark.
Finally, we end up at strikeout and walk rates. Surprise, surprise, Group A has been inferior here, striking out fewer, while also walking more. Actually, it’s not a surprise at all because with underwhelming strikeout and walk rates, they needed help from the luck metric trio in order to post an aggregate sub-3.00 ERA!
Group A is filled with some of this season’s biggest surprises. Reynaldo López was a full-time starter from 2017 to 2020, but just once posted an ERA below 4.00, and it was barely below. After spending several years in the bullpen, he’s back in the rotation and…suddenly an ace?! The skills here have been solid, and probably better than anyone expected, but clearly this sub-2.00 ERA is wholly undeserved. He’s leading baseball in LOB% and that’s just not something you can count on continuing.
Silly me for thinking that Ronel Blanco’s no-hitter in his first start of the year would result in wasted FAAB money, as he gets dropped just a couple of weeks later. Oops! The skills here are nothing special, but that .178 BABIP is absurd. His xERA is better than his SIERA, suggesting he is deserving of some of that BABIP, but obviously not all of it. He ranks 14th in HardHit% against, 79th in Barrel% against, and 35th in EV against. None of those numbers suggest a BABIP beast. If I’m at or near the top in the ratio categories and have Blanco partly to thank, I would aggressively look to trade him as you’ve already received all the benefits you ever will.
You probably had no idea that Corbin Burnes is sitting on the lowest strikeout rate of his career (ignoring his 2018 debut of 38 innings). His BABIP has now been better than average for several years running, but his LOB% sits at a career best (again ignoring that 2018 debut). His xERA is also better than his SIERA, but the drop in strikeout rate, which had already dropped dramatically last season, really cuts into his value.
Moving onto the underperformers, it’s absolutely hilarious to find Kyle Hendricks atop the list. He used to be the poster boy for SIERA overperformance, so this is a complete 180. His appearance here is precisely why I always want to buy underlying skills (strikeouts, walks, batted ball profile), because you never know when the softer skills, like suppressing hits on balls in play or home runs on fly balls, will deteriorate.
Pablo López seems like the ultimate rest of season target. There are no red flags here and no explanation for the inflated HR/FB rate or career worst LOB%, other than a run of poor fortune. He has mostly maintained last year’s velocity spike and his pitch mix remains stable. He has posted the highest FB% of his career, which should have reduced his BABIP, but it hasn’t, while his second highest HR/FB is exacerbated by the higher mark. BUY BUY BUY.
With a 31.9% strikeout rate, matching his career best, I don’t think it’ll be easy to buy Dylan Cease at a discount. The skills look as strong as ever and he’s even thrown the highest rate of strikes in his career, reducing his walk rate to a career best. His fastball velocity has rebounded after dipping last year as well. The biggest issue is a sub-70% LOB%, which is probably the most luck-involved metric of the trio. If there’s any discount to be had given the 3.99 ERA, run, don’t walk, to take advantage.
So which group performs better over the rest of the season? Let’s get to the poll questions. Feel free to share your poll answers and why you voted the way you did.
Mike Podhorzer is the 2015 Fantasy Sports Writers Association Baseball Writer of the Year and three-time Tout Wars champion. He is the author of the eBook Projecting X 2.0: How to Forecast Baseball Player Performance, which teaches you how to project players yourself. Follow Mike on X@MikePodhorzer and contact him via email.
Good stuff, Mike. I expect Group B to have a better composite ERA than group A. But notably, only Pablo and Cease strike me as having truly elite skills. (In fact I believe Cease to be among the 8–10 best SP this season on skills, though he’s rarely ranked that way). I have a lot of Pablo; really hope he’s not cursed ROS. Will look for your follow up.