Paul Skenes posts 5.36 ERA over last 47 innings, with competing theories about why

What happened

Paul Skenes has not looked like himself since May 12. That evening, pitching at home against the Rockies, he threw eight shutout innings, allowed two hits and no walks, and struck out 10. It was, by any measure, a dominant performance. What has followed is the subject of considerable debate.

Per FanGraphs, Skenes has posted a 5.36 ERA over 47 innings since that start. He has failed to reach six innings in six of his last nine outings, and home runs have piled up during that same stretch — seven of his 11 allowed on the season have arrived in that span. The numbers represent a meaningful departure from the pitcher Pittsburgh has been counting on, and the baseball world has been working to figure out what, exactly, is behind it.

Why it matters

The honest answer, per FanGraphs, is that nobody is entirely sure — and that uncertainty is itself the story. The outlet identifies several competing theories circulating around Skenes's recent struggles, none of which has been settled. The piece does not diagnose. Neither should anyone reading it.

One school of thought points to the defense behind him. Skenes has reportedly been on the mound for several obvious defensive miscues, and proponents of this view cite his expected statistics as evidence that batted-ball luck has worked against him. On this reading, the underlying stuff is fine; the results have been distorted by factors outside his control.

A second theory holds that something mechanical has shifted in his delivery. Mechanical drift is a familiar enough phenomenon for starting pitchers — the kind of thing that can creep in over a long season and compound quietly before it becomes visible in the ERA column.

The third theory is the one that tends to focus minds: that Skenes may be pitching through a physical ailment. FanGraphs does not present this as a finding, and no announcement from the Pittsburgh Pirates has been reported. It remains, as the outlet frames it, one of several competing explanations — but when a young pitcher's performance drops and the cause is unclear, that particular theory tends to linger in the room.

It is worth sitting with that uncertainty rather than resolving it prematurely. FanGraphs is explicit that the question of what is actually wrong, if anything, remains open.

The numbers

The season line tells the story of two pitchers sharing one roster spot. Through May 12, Skenes was the version of himself that had generated genuine excitement in Pittsburgh. Since then, the 5.36 ERA over 47 innings represents a stretch that would be concerning for any starter, let alone one carrying the expectations Skenes carries.

The home run rate is particularly notable. More than half of his 11 home runs allowed on the season have been concentrated in roughly the last month and a half of work. Whether that reflects a mechanical issue, a pitch-tipping problem, a change in how hitters are approaching him, or simply the hard contact that follows defensive breakdowns is, again, one of the open questions.

The innings-per-start figure adds another layer. Exiting before the sixth inning in six of his last nine turns through the rotation puts additional strain on a Pittsburgh bullpen that is being asked to cover more ground than it was earlier in the season. For a team that enters Tuesday's game against Atlanta at 82-80, every start that falls short of six innings has downstream consequences.

Where the club stands

The Pirates carry an 82-80 record, which places them third in the NL Central and 21 games back in the division. They have been eliminated from both the division race and the Wild Card race, sitting fifth in Wild Card positioning at 6.0 games relative to the cut line. They enter Tuesday on a one-game winning streak.

None of that context makes the Skenes situation easier to read. A team still playing out a .506 season has a different relationship with a struggling front-line starter than a club that has already turned the calendar fully toward prospect evaluation. Pittsburgh occupies an ambiguous middle space: not contending, not fully rebuilding, and leaning on Skenes as both a present asset and a long-term cornerstone. The combination of those two facts — a season that is technically alive in the standings and a starter whose recent numbers invite real questions — gives the next several weeks an unusual amount of weight.

What we don't know yet

The central unknown is the one FanGraphs names directly: what is actually causing the decline. The physical ailment theory has not been addressed in any capacity by the Pirates organization, per the reporting. There has been no announcement, no injured list placement, no public acknowledgment from the club that anything is wrong physically. That silence does not resolve the question in either direction.

The mechanical theory is similarly unaddressed in the public record. Pitching coaches and analysts can identify delivery changes in video, but whether any such change has been identified internally — and whether it is being worked on — is not part of what has been reported.

The defensive-luck theory is the most testable of the three, in the sense that expected statistics can be examined. But even that framing leaves room for debate about how much weight to assign those numbers over a stretch of 47 innings.

What FanGraphs is careful to preserve, and what any honest accounting of this situation must also preserve, is that these theories are not mutually exclusive. A pitcher could be dealing with a physical issue that subtly alters his mechanics, which in turn produces different batted-ball profiles, which then interact with defensive miscues in ways that inflate the ERA beyond what any single cause would explain. The real answer may be some combination of all three — or something else entirely that has not yet been named.

What to watch

### Is Skenes starting Tuesday against Atlanta?

Per the schedule, yes — Skenes is listed as the probable starter for Tuesday's game at PNC Park against the Braves, with Hurston Waldrep going for Atlanta. That start will draw significant attention given the recent stretch, and it will offer another data point for the competing theories. Observers will be watching pitch shape, velocity, and whether the home run and short-outing patterns continue.

The Atlanta series runs through Thursday, with Jared Jones probable against Grant Holmes on Wednesday and Mitch Keller probable against Bryce Elder on Thursday. But Tuesday belongs to Skenes, and the questions that FanGraphs has laid out will be very much alive from the first pitch.

The physical ailment theory, in particular, is worth monitoring. If the Pirates make any roster move involving Skenes — or if the club offers any public comment on his health — that would represent a meaningful development beyond what the current reporting establishes. For now, the theories are competing, the 5.36 ERA since May 12 is the only number anyone can agree on, and the next start is on the horizon.