It was the evening of May 12 when Don Kelly was asked to compare his star player to the best pitcher Kelly had ever shared a clubhouse with.

Paul Skenes had been brilliant once again, allowing just two hits while striking out 10 over eight scoreless innings against the Colorado Rockies. It felt like we weren’t only witnessing the continuation of Skenes’ dominance but perhaps the beginning of him elevating his game to an even higher level.

All we’d seen from the Pirates’ right-hander was excellence. At that time, no achievement seemed out of reach for the reigning National League Cy Young winner.

I remember watching Skenes mow down the Rockies that evening. I remember thinking his 2026 campaign could go down as one of the greatest pitching seasons in league history, right up there with Bob Gibson in 1968, Pedro Martinez in 1999 and Justin Verlander in 2011. I remember bringing these thoughts up to Kelly following his club’s 3-1 victory. And I remember Kelly offering a similar sentiment.

“Every time [Verlander] took the mound, you were shocked when he gave up a hit,” said Kelly, who played with Verlander during the 2011 season. “Paul is on that type of run right now. Just the way that he’s throwing the ball — commanding the zone, too — and then being able to mix it up with all of his pitches, it’s impressive to watch.”

But after that outing, a different type of run started — one we hadn’t seen before.

Those eight innings of near perfection on May 12 mark the last time the Pirates won a game with Skenes on the hill. They’ve lost each of his following nine, the most recent start undoubtedly his worst.

The Pirates are a worse baseball team when Paul Skenes is on the mound.

Let that sink in.

They are 6-12 in his 18 starts this season. Their record is well over .500 in games when he’s not involved. Skenes’ shortcomings have become impossible to ignore.

Many are wondering what is wrong. Few seem to know how this can be fixed. For the first time in his Pirates career, there is legitimate reason to be concerned about Skenes’ ability to help them win games.

So I combed through the numbers and chatted with a few sources, all with the goal of learning one thing.

Who is to blame for this shocking decline?

The defense?

While Skenes has been roughed up a few times throughout this stretch, resulting in a 5.36 ERA over his last nine starts, not every outing has been terrible. His metrics are mostly similar to what they were last season — save for a few key details that will be covered later on.

He’s tallying more strikeouts and issuing fewer walks. His opposing batting average on balls in play (BABIP) and walks plus hits per inning pitched (WHIP) are about equal to last season’s marks. His expected earned-run average (xERA) and expected fielding-independent pitching (xFIP) both rank within the top 10 of MLB.

But all of these fancy statistics mean very little when the Pirates’ defense gets involved.

Per Baseball Savant, the Pirates have a minus-5 fielding run value when Skenes is on the mound. That’s the worst defensive support for any starting pitcher in the National League and third worst in all of MLB. When reviewing some of his other metrics, I noticed a few sizable dips surely impacted by this.

Last season, Skenes stranded 82.4% of the runners he allowed to reach base. His clutch metric, a stat on FanGraphs that measures how well a pitcher performs in high-leverage situations, was 0.53. Skenes ranked top 10 in MLB for both figures in 2025. Watching him dance out of a jam was essentially part of the viewing experience, something he hardly ever failed to achieve.

This year is much different. Skenes’ left-on-base percentage is down to 65.8%, which ranked 58th among MLB’s 64 qualified starting pitchers entering Thursday. His clutch factor sat at minus-0.60 after Wednesday’s loss, ranking him 54th among that bunch.

Make no mistake, Skenes has to be better. But this year’s defense hasn’t made things any easier on him. There have been times when Skenes needed his fielders to pick him up, to help him out in a bind. More often than not, they’ve let him down.

The coaching?

At the end of last season, the Pirates shocked many by parting ways with longtime pitching coach Oscar Marin. The decision, as reported by the Post-Gazette, was heavily influenced by feedback from players on the active roster.

There was a group within the clubhouse that believed the pitching staff could reach another level and change was required in order for this to happen. Per multiple sources, Skenes was a part of that group.

Skenes expressed his pleasure with Bill Murphy’s hire on the night he was announced as the 2025 National League Cy Young Award winner. He echoed those thoughts throughout spring training, indicating he believed Murphy was the upgrade his team was searching for.

Then the regular season arrived.

It’s never easy to quantify how responsible coaches are for the success or failure of an individual player. That said, it’s rather difficult to highlight any specific area where Skenes has noticeably improved under Murphy’s watch.

None of Skenes’ pitches are as effective as they were in 2025. Numerous pitching analysts have highlighted potential mechanical flaws in his delivery, ones that could have led to a dip in command.

The fact these issues have persisted over a month doesn’t exactly reflect well on Murphy.

Skenes’ brilliance from the moment he arrived to the major leagues allowed many of us to forget just how young he is, both as a human and a pitcher. Four years ago, he was a two-way player at Air Force. While his first three seasons solely as a pitcher went historically well, he was due to hit some adversity at some point.

That adversity has arrived.

Skenes is far from the only Pirates pitcher who has regressed in 2026. But his shortcomings are amplified due to his status within the game. Right now, it seems as though this coaching staff can’t help Skenes — a man whom many considered to be the best pitcher on the planet — get back to his old form.

I won’t pretend to know what the Pirates are doing to help Skenes behind closed doors. They’re likely exploring every avenue, from film study to analytical deep dives to biometrical data to perhaps even new mental health strategies, all in the effort of getting the franchise’s best player back on track.

But as this losing streak continues, it’s looking more and more like their plan might not be working.

The player?

While Skenes’ physical build is the ideal prototype for a “power pitcher,” his preparation and attention to detail are what truly separate him from the pack. But right now, he seems a bit lost.

As noted above, every single pitch Skenes throws has regressed in 2026. His fastball velocity is lower than ever before, something he claimed was by design, per a report by DK Pittsburgh Sports. Whether you believe him, that lesser velocity has led to lesser results.

The biggest difference in Skenes’ advanced metrics pertains to home runs allowed. Last season, he surrendered just 0.53 long balls per nine innings, the best average among all qualified starting pitchers in MLB. This year, his HR/9 currently sits at 1.02, which ranks 36th out of 64 total.

Skenes’ fastball is the main culprit. Opposing hitters have taken his four-seamer yard five times this year, matching last year’s total. There have been multiple outings this season when his primary pitch was lacking command — Wednesday’s loss being the most obvious example.

All this said, his fastball is still his best pitch, if by nothing else than default.

In 2024, Skenes took the baseball world by storm as a rookie while throwing four pitches for at least 10% of his overall usage — a four-seamer, a “splinker,” a curveball and a sweeper. Two are no longer a reliable part of his arsenal.

Not long ago, Skenes’ splinker was viewed to be among the most lethal pitches in baseball. The split-sinker hybrid became the subject of countless articles and highlight reels. In 2025, he aimed to further expand his pitch mix, spending the offseason following his rookie year working to develop a sinker and cutter.

The latter never truly stuck. The former may have damaged his bread and butter.

Once nearly unhittable, opponents are batting .366 against Skenes’ splinker in 2026. His sinker isn’t much better, offering a .444 opposing slugging percentage, the highest of any pitch in his arsenal.

The curveball, meanwhile, is no longer an option. Skenes has thrown it just 10 times in 2026, a remarkably steep drop from when it accounted for 16% of his total workload as a rookie. His decision to do away with the curve wasn’t exactly a bad idea — opposing batters slugged .680 against the pitch in 2025. But unlike last year, there is nothing else to lean on.

Skenes’ sweeper and slider are getting similar usage, but neither has proven to be a quality second pitch in 2026. He’s relied more on his change-up as a result, which currently sits at a minus-2 run value, per Baseball Savant, making it his lowest-rated pitch on the season.

All this said, it’s worth wondering: How much is Skenes getting in his own way?

After accomplishing so much so early into his career, is it possible he stretched himself too thin? In an attempt to master every element of the game, did he unintentionally dilute his overall skill set?

That would explain why his pitch quality — something that once made him the best of the best — has suffered in 2026. But that’s just one columnist’s theory.

In the end, the only person who is going to fix Skenes’ struggles is Skenes himself.

The defense can certainly be better, and it’s absolutely worth questioning if this slump would have occurred under Marin’s coaching. But right now, Paul Skenes doesn’t look like Paul Skenes, not on the mound or in the box score.

The Pirates are a better team on the days Skenes is not pitching — a sentence few could’ve ever imagined to be true. That, however, is the reality the 2026 Pirates face.

And in order for this club to have any true hope at reaching the postseason, Skenes must be the one to turn his campaign around.

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