MLB Pitcher Studs and Duds - Advanced Metrics Leaders for ERA-xERA (Week 19)

August 16, 2022

Connelly examines fantasy baseball pitcher risers and fallers, whose ERA-xERA could make them adds, drops, or trade targets for Week 19.

Welcome back to fantasy baseball and RotoBaller’s Statcast Pitcher Studs and Duds article series! Each week, I select one advanced metric, choose two pitchers with strong values and two with poor values, and analyze what those values may mean for future performance.

I wrote about expected ERA (xERA) in Week 10; xERA is a 1:1 translation of Expected Weighted On-Base Average (xwOBA), converted to the ERA scale. Like any expected metric, comparing it to the actual metric gives an indication of relative over or underperformance for players.

This exercise is great for identifying buy-low and sell-high fantasy pitchers. The fantasy playoffs are quickly approaching, but there is still a month and a half of the season left for regression to take place. Let's identify some pitchers who may see that in their ERA! 

ERA-xERA Studs for Fantasy Baseball

All stats are current as of Sunday morning, August 14, 2022.

Alex Cobb, San Francisco Giants
3-6, 4.15 ERA, 2.97 xERA, 1.18 ERA-xERA

Alex Cobb's peripheral numbers have lagged behind his underlying stats for much of the season, and his ERA has been no different. His 4.15 ERA and 1.29 WHIP are mediocre, but his xERA is over a run lower than his current ERA. Cobb is currently rostered in just 36 percent of leagues, but is there enough time for fantasy managers to experience the potential regression?

I am frankly very surprised that Cobb is still so widely available. Even a quick look at his profile shows the signs of an above-average pitcher, as indicated by all the red in his Statcast profile. He has managed to keep the ball on the ground with a 0.0-degree launch angle while still posting a respectable 25.3% strikeout rate, thanks to relying on a split-finger fastball (44.3% usage) and a sinker (42.6% usage).

Additionally, he has already clearly started to experience that regression. Cobb has compiled a much-better 3.26 ERA, 1.09 WHIP, and 29.8% strikeout rate in his five starts since the All-Star break. This is even more encouraging given the fact that his 2.76 SIERA over those starts indicates that he was still getting a bit unlucky in his results over that time.

Fantasy managers will likely have to make some last-minute trades to gain impact fantasy players on their teams at this point in the season. The fact that a pitcher of Cobb's caliber is so widely available at this time is crazy to me but offers a fantastic opportunity for fantasy managers. I consider Cobb to be a strong buy-low candidate and it appears that fantasy managers won't even have to trade for him.

Dylan Bundy, Minnesota Twins
6-5, 4.76 ERA, 3.86 xERA, 0.90 ERA-xERA

Dylan Bundy has has a disappointing career overall from a fantasy perspective, but he has been valuable at times. On paper, this season has not been one of them, as he has managed a lackluster 4.76 ERA through 20 starts with the Twins. However, his 3.86 xERA suggests that he could outperform those paper numbers by a decent mark for the rest of the season. Could Bundy be a worthwhile streamer for fantasy managers down the stretch?

Bundy's underlying metrics are not as cut and dry as some of the other guys in this article. The issue for Bundy has been home runs, which has been an issue for him in the past. His 1.37 HR/9 rate could be attributed to the hard contact he has allowed with an 18.2-degree launch angle. His 4.32 SIERA seems to reflect this more than his xERA.

Walks haven't been an issue for Bundy at a 5.0% clip, so he would likely be able to last at least five innings per start if he could get those HR in order.

Some of Bundy's underlying numbers are more encouraging than others. Ultimately, his batted-ball profile has hurt him, although his xERA suggests it may not be as big of a deal as the peripherals suggest. To me, the batted-ball profile and peripheral results align too much for me to take a flyer on Bundy except in deeper leagues and in very favorable matchups.

ERA-xERA Duds for Fantasy Baseball

All stats are current as of Sunday morning, August 14, 2022.

Cole Irvin, Oakland Athletics
6-9, 2.92 ERA, 4.23 xERA, -1.31 ERA-xERA

Cole Irvin has been an impactful fantasy pitcher this season despite playing on one of baseball's worst teams. He hasn't helped much in terms of strikeouts but has compiled a stellar 2.92 ERA and 1.03 WHIP in 20 starts. Fantasy managers are buying in, as his 61 percent rostership is almost twice that of Cobb's. However, his 4.23 xERA is much worse than his current ERA. Should fantasy managers continue to trust him down the stretch?

While it is always possible that players will exceed their projected numbers over the course of an entire season, I would still be uneasy about trusting Irvin in the fantasy playoffs. Unlike Cobb, most of Irvin's Statcast profile is very blue. He has gotten strong results despite allowing hard contact with a 14.7-degree launch angle.

Irvin has managed to last just over six innings pitched per start, which has somewhat helped him in terms of strikeouts totals. However, he relies primarily on underwhelming fastballs, which he has left in the middle of the plate. As such, I am not surprised by his 17.2% strikeout rate and would not be surprised to see him run into some short outings over the course of the rest of the season.

I feel almost as strongly that Irvin is a sell-high candidate as I am that Cobb is a buy-low candidate. Irvin has gotten solid results while pitching deeper into games, but most underlying signs point to him being the beneficiary of luck. He has allowed hard contact in the air while not striking many out.

This seems to be a recipe for disappointment in fantasy. Again, there is the chance that Irvin can finish out the season with strong numbers, but I would rather trade him for more proven, reliable fantasy options.

Johnny Cueto, Chicago White Sox
4-5, 2.91 ERA, 4.06 xERA, -1.15 ERA-xERA

Johnny Cueto was a fantasy stud for a good chunk of his career, and while his last several seasons have not been to that standard, he seems to have recaptured some of it this season. The crafty veteran has compiled a 2.91 ERA over 15 starts while averaging almost 6 1/2 inning per start. However, his 4.06 xERA suggests he maybe hasn't recaptured his old magic and he is currently rostered in just 51 percent of leagues. Could Cueto be more of an asset or a liability for fantasy managers the rest of the way?

Cueto is interesting because he has done a decent job keeping hitters off balance. He has thrown five pitches at least 14 percent of the time and varies his delivery. Consequently, his exit velocity and hard-hit rate are both slightly above average with a 12-degree launch angle despite not having overpowering stuff. He has also done a good job limiting walks with a 5.6% walk rate.

The thing that could hurt Cueto is the amount of contact he allows. As I mentioned, his batted-ball profile is fine, but his 84.8% contact rate would be the highest among qualified starters if he were eligible. As such, he has a 1.22 WHIP and a .292 BABIP which is above his career mark of .284. His ERA shows that all those hits haven't hurt him, but his xERA indicates that they may.

Cueto is no longer a flashy fantasy option, but he does still have something to offer. He has allowed a lot of hits but has managed to navigate the traffic and pitch deep into games, which creates more opportunities to earn wins for fantasy managers. The hits and lack of strikeouts obviously limit his fantasy value in all leagues, but I think he offers a solid floor in points leagues and could continue to provide that, even if a few more of those hits turn into runs.

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