Starting Pitchers: Better than Expected

Similar to hitters, traditional pitching metrics get all the focus in fantasy baseball when the advanced stats have proven to be more indicative of future success. The game has moved in this direction from a front office perspective and the same should be done in fantasy. In this article, the focus will be ERA compared to the advanced metrics FIP, xFIP and SIERA.

ERA is a valuable but antiquated statistic. Before advanced metrics were available, runs allowed and innings pitched, other than strikeouts, were the best estimate of pitchers’ success. WHIP came along in 1979 and was backdated to all prior seasons because walks and hits were always recorded. In today’s game there is a surplus of information and statistics for the taking yet fantasy GMs still tend to focus on ERA over the other metrics listed because they understand how it works. The reality is that there is so much more that goes into pitcher success – defense, luck and park factors to name the main three – and neglecting those aspects by relying solely on ERA ignores valuable data. FIP, xFIP and SIERA attempt to account for all that.

I’ve teased these stats but what exactly are they? Their definitions and formulas are as follow, taken directly from Fangraphs:

1. Fielding Independent Pitching (FIP) is a statistic that estimates a pitcher’s run prevention independent of the performance of their defense. It is generally a better representation of performance than ERA. FIP = (13 x HR + 3 x (BB + HBP) – 2 x K) / IP + FIP Constant.
2. Expected Fielding Independent Pitching (xFIP) differs from FIP in that it normalizes a pitcher’s home runs allowed based on their fly ball rate rather than simply using the raw number of home runs allowed. xFIP = (13 x (Fly Balls x LgHR/FB%) + 3 x (BB + HBP) – 2 x K) / IP + FIP Constant.
3. Skill-interactive ERA (SIERA) attempts to answer the question: what is the underlying skill level of this pitcher? While it is only slightly more predictive than xFIP, SIERA tells us more about the how and why of pitching. The SIERA calculation is too complicated to list.

To demonstrate the differences between the four stats, take 2020 rookie Kwang-hyun Kim and his starting-pitcher-leading 1.42 ERA among the 165 starters with at least 20 innings. Kim’s 3.9 FIP was still above average, but his 4.55 xFIP and 5.02 SIERA were both below the 40^th percentile. Looking at ERA alone, Kim profiles favorably even if a repeat of last season’s ERA isn’t realistic. A deeper dive reveals that the rookie’s ERA is an inaccurate estimator and most likely a product of small sample size, a trend to be wary of when considering last season’s 60-game ledger. Below you will find 10 starters who are likely due for a rebound in 2021 and are currently available later in drafts than their peripherals indicate.

Tyler Glasnow SP, TB | ERA: 4.08, FIP: 3.66, xFIP: 2.75, SIERA: 3.04

Glasnow is one of the best strikeout artists in the game and many pegged him as a breakout candidate last season. His 38.2 K% ranked third among all starters and all of his advanced metrics are better than his more available ERA with an emphasis on his sixth ranked SIERA. Despite the bloated ERA, Glasnow still finished 18^th in FPPG last season and is currently going  15^th in starting pitcher ADP. A leap in the run prevention department could vault the 6’8 righty into the positions top 10.

Kenta Maeda SP, Min | ERA: 2.7, FIP: 3, xFIP: 2.63, SIERA: 2.92

It’s easy to forget that Maeda finished a distant second to Shane Bieber in AL Cy Young voting last year, which makes his current slot at 16^th among starters understandable. The advanced numbers show a slight regression in ERA but a still well above average FIP of 3. A sixth round ADP makes Maeda a solid value on draft day.

Corbin Burnes SP, Mil | ERA: 1.72, FIP: 1.64, xFIP: 2.59, SIERA: 2.99

Burnes’ breakout 2020 was cut short by an oblique injury but that didn’t stop him from posting a league-leading FIP and a top five SIERA in nine games as a starter. Similar to Maeda, Burnes’ advanced metrics aren’t quite as good but are still more than respectable. The small sample size of nine starts is also a concern but an eighth round ADP makes him a potential breakout pick.

Kevin Gausman SP, SF | ERA: 3.62, FIP: 2.94, xFIP: 2.96, SIERA: 3.18

Gausman experienced a huge bounce back campaign in 2020 with the Giants that he was able to parlay into a rare qualifying-offer acceptance. He was one of the rare starters to experience a better rate in each of the three advanced stats than in ERA and was still able to post a near top 30 FPPG season regardless. Despite the success, a current 19^th round ADP makes him an easy late-round upside pick.

Andrew Heaney SP, LAA | ERA: 4.45, FIP: 3.79, xFIP: 4.15, SIERA: 4.08

Heaney is one of those players who’s expected to breakout each season but lacks the consistency to truly do so. Part of the reason is a FIP that is historically better than his ERA, a curious development. Over the past three seasons Heaney sports a 4.42 ERA and 4.13 FIP which isn’t as extreme as his 2020 season but carries more weight due to the larger sample. Heaney finished 60^th in FPPG and is currently going as starter 51 after pick 200, worth the risk of a late round pick when considering the potential return.

Zach Eflin SP, Phi | ERA: 4.15, FIP: 3.3, xFIP: 3.09, SIERA: 3.41

Like Burnes, Eflin pitched a bit in relief last season, and these are his numbers solely as a starter. The ERA is decent but it’s the superb, advanced stats that make Eflin a potential value pick as the most impressive is his 20th ranked SIERA. He’s currently going one spot after Heaney and probably comes with more upside.

Aaron Civale SP, Cle | ERA: 4.74, FIP: 4.03, xFIP: 3.92, SIERA: 4.11

Civale tailed off last season after a scorching start and could be the next breakout Cleveland starter. The advanced stats don’t exactly jump off the page but are respectably better than a below-average 4.74 ERA. A current draft slot of 223 makes him a favorable late round selection.

Framber Valdez SP, Hou | ERA: 3.92, FIP: 3.02, xFIP: 3.03, SIERA: 3.33

 Valdez seemingly came out of nowhere to post a 2020 breakout that resulted in an 11^th place finish in Cy Young voting, yet he’s barely being drafted in half of leagues (54.7 % ROST) at an ADP of 259. This is a top 30 starter in FPPG last year that could be even better according to the numbers and performed well in four postseason starts. The catch is Valdez fractured a finger fielding a hard groundball off the bat of Francisco Lindor early in spring training. He avoided season-ending surgery but is likely out at least two months. If you can stash Valdez until he’s ready, you can reap some second half benefits..

Yusei Kikuchi SP, Sea | ERA: 5.17, FIP: 3.3, xFIP: 3.78, SIERA: 4.34

Kikuchi was horrible in a hyped 2019 rookie campaign and performed much better last season, even if that isn’t completely apparent on paper. He finished as a top 100 starter last year and won’t blow anyone away but isn’t being drafted in most leagues and only has a 5 % ROST.

Luke Weaver SP, Ari | ERA: 6.58, FIP: 4.67, xFIP: 5.06, SIERA: 4.52

Even Weaver’s advanced stats were bad last season, but it’s clear the potential is there thanks to strong 2017 and 2019 seasons, albeit in around 60 innings each. Worse options exist for someone who’s hardly being considered yet Weaver is still relatively young and was a decent option over the last few years.