As the 2026 season approaches its midway point, analysts at FanGraphs have turned to a more nuanced set of metrics to separate genuine starter talent from fleeting luck.
Two distinct cohorts emerge when sorting starters by their SIERA over‑ and under‑performance: Group A, the ten biggest SIERA overperformers, and Group B, the ten biggest SIERA underperformers.
The profile of the overperformers
Pitchers in Group A share a common fingerprint: lower home‑run‑to‑fly‑ball rates, suppressed BABIP and elite left‑on‑base percentages. Eduardo Rodriguez exemplifies this paradox, posting a modest ERA while his expected ERA sits at 5.06, indicating a skill set that is simply undervalued by traditional counting stats.
Walbert Ureña, another member of the cohort, enjoys a similarly low BABIP and HR/FB rate, yet his xERA aligns much more closely with his actual ERA, suggesting that his luck has been relatively modest.
Justin Wrobleski has nudged his SIERA upward, but the underlying model still flags a sizable luck component, reminding us that even rising metrics can mask underlying volatility.
Michael McGreevy’s profile is a study in risk: a high LOB% paired with a low Stuff+ makes him an enticing but precarious fantasy asset, especially as the league’s defensive standards continue to shift.
Sonny Gray, enjoying a career‑best ERA, is simultaneously posting a strikeout rate that lags behind his peers and a LOB% that remains elevated, a combination that could unravel once regression sets in.
Kyle Freeland’s SIERA marks the pinnacle of his career, yet his ERA remains unattractive, underscoring why he is a poor pick despite the advanced metric’s endorsement.
David Peterson’s SIERA is, by most measures, ugly, and his xERA is even higher, painting a bleak outlook for a pitcher who has yet to translate promise into performance.
The underperformers’ dilemma
Aaron Nola’s sub‑par SIERA and xERA can be traced to the Phillies’ porous defense, a factor that has turned a normally reliable starter into a liability for fantasy managers.
Roki Sasaki’s high HR/FB rate raises eyebrows, but recent improvements in his pitch‑model outputs hint at a pitcher who may yet refine his approach.
Emmet Sheehan’s slightly elevated HR/FB rate is offset by league‑average marks in other categories, positioning him as a steady, if unspectacular, option in deeper leagues.
The remainder of Group B includes names such as Nick Martinez, Robbie Ray, Shohei Ohtani, Tyler Phillips, Keider Montero, Jeffrey Springs, Michael Lorenzen, Zac Gallen, Mike Burrows, Walker Buehler, José Soriano and others, each presenting a unique blend of strengths and vulnerabilities that will shape their second‑half narratives.
For fantasy owners and front‑office analysts alike, the takeaway is clear: relying solely on ERA can be misleading. SIERA offers a more stable gauge, but its true power lies in contextualizing the surrounding variables — defense, luck and pitch‑design evolution — that ultimately dictate a starter’s trajectory.