Which pitchers might see their ERA rise along with the temperature?

A couple of years ago, Major League Baseball wasn’t happy with the run-scoring landscape. As a result, several rules were instituted following the 2022 season with the intent of increasing the numbers of runners crossing the plate. Legislating the shift, adding the pitch clock, increasing base size and limiting disengagements from the rubber all helped to push up overall scoring.

This year, despite continuing to carry over those rules adjustments, overall scoring is somehow trending back down. Home runs are lagging and, digging deeper, we see that the average fly ball distance is over two feet lower than it was at this same point of the season in 2023. It’s also about six inches lower than at the same time in 2022 and a whopping 10 feet shorter than in 2019, when home runs soared.

There are various factors influencing the flight of the baseball. High temperatures and humidity help the ball travel further, which is historically borne out with the numbers, including this season. The ball itself is also a major influence. The weight of the ball, the height of the seams and how tightly it is wound all have an impact on distance.

In 2019, studies verified that there had been changes made to the ball, helping to facilitate greater distances — and, hence, more souvenirs for fans sitting in the bleachers. So far this year, there doesn’t appear to be any scientific evidence explaining the results but, anecdotally, while fly balls are exhibiting the same average exit velocity, they’re just not traveling as far.

Something else out of the norm is occurring this year. The BABIP (batting average of ball in play) on fly balls has plummeted compared to recent seasons. While it is possible that it’s simply variance that is the driving force, this trend suggests that teams have merely adjusted by playing closer to the infield. This has resulted in more softly hit fly balls being caught while still allowing outfielders to track down balls sent over their head. In June, fly ball BABIP has been on the upswing, most likely piggybacking on weather-induced increase in flight.

Rising to the challenge

Relating this to managing our fantasy baseball teams, many consider a pitcher’s ability to induce ground balls as a beneficial skill. More ground balls means fewer home runs and an increase in double plays. However, it’s also true that far more grounders become hits compared to fly balls. A fly ball pitcher who limits walks and misses bats can be just as effective as a ground ball specialist. In fact, if a fly ball pitcher works in a big venue with solid defenders, he may actually be preferred to a ground ball hurler.

So far this season, fly ball pitchers have been reaping even more benefits than usual. Not only are they surrendering fewer long balls, but they’re generating more fly ball outs. Past season’s doubles and triples are finding leather.

In other words, the way the baseball is performing might help explain the surprising performance of several pitchers, especially those who limit walks. Relative to recent years, fewer runs are coming courtesy of the home run. Teams need to generate more traffic on the basepaths to score, so the pitchers who are not giving away free passes have been garnering even more of an edge.

The caveat is that arms of this ilk will be disproportionately burdened over the hotter months of summer as the average fly ball distance increases. Yes, on paper, every pitcher will be negatively affected — perhaps not all to same extent, but overall scoring will likely continue to edge up in July and August before sliding back a bit in September.

How can these pitchers stay grounded?

What follows is a review of some pitchers with low ground ball rates who may end up getting hurt the most by summer’s increase in fly ball travel. Now, the forecast isn’t “doom and gloom” across the board, but it helps to have a feel for what may be in store for these guys over the second half of the season.

Luis Gil, New York Yankees: Gil is being mentioned as a candidate to start the All-Star Game, not to mention he’s currently a Cy Young darling. There is no denying that Gil has impressed with a 29.3% strikeout rate, ninth-best among pitchers with at least 50 IP. However, his 12.4% walk rate is fourth-worst in that group and he’s been blessed by Lady Luck. Gil is sporting a .222 BABIP and a 7.1% HR/FB. Both of those are already due for an increase, even before the expected summer increase in average fly ball distance.

When someone is performing at Gil’s level, there’s a tendency to downplay the “good fortune” aspect and overemphasize the skill. Plain and simple: Gil has been both very good … and very lucky. Trading away a guy with a 2.77 ERA and 97 strikeouts over 81 1/3 frames may seem like a bad idea, but at some point, the Yankees will have to cut back on his innings, so that he can remain fresh for the playoffs. In keeper leagues, shopping Gil to a team in rebuild mode could net you a championship.

Nestor Cortes, Yankees: Here’s a great example of how limiting walks embellishes the benefits of the perceived deader ball. Cortes’ 4.5% walk rate is 11th-lowest overall, but his 23.1% strikeout rate is just a bit better than average. His 29th-ranked 18.6% K-BB% is solid, but relies on that career-low walk rate. Cortes’ 9.2% HR/FB is due for a little regression, but with a soaring 49.3% fly ball rate, the effect on his current 1.16 HR/9 could be compounded. Selling high is always easier said than done, but Cortes’ rest-of-season ERA should be at least half a run higher than its current 3.40 level.

Bailey Ober, Minnesota Twins: Ober is intriguing on several levels. As an extreme fly ball pitcher, he’s more subject to the looming effects of the ball traveling further. However, he didn’t take full advantage of the benefits over the first half. In other words, he’s actually a candidate for generating better second half numbers to help mitigate the impact of the increase flight of the ball.

Ober’s 3.91 xFIP and 3.67 SIERA indicate that his actual 4.50 ERA is undeserved. This doesn’t mean an ERA in the range of those estimators should be expected, since that assumes he will pitch with the same skills as in the first half (and that’s not guaranteed). However, if the narrative is that Ober’s ERA is due to increase with increased fly ball travel, then the baseline from which to start is that of his estimators and not his current mark.

Ober is more dominant than many fly ball pitchers, helping to offset some of the impending damage. Even so, while he’s likely to post better numbers in the second half, he’s not someone to rely upon to significantly improve.

Joe Ryan, Twins: Ryan is a top-20 starting pitcher, so if the baseball scoots a few more feet? That isn’t going to change that truth. That said, Ryan will be hard-pressed to maintain his current 3.13 ERA. His 3.29 SIERA and 3.40 xFIP show that the fall should be cushioned but, again, that factors in similar skills. An area due for regression is Ryan’s .254 BABIP.

Yes, fly ball pitchers should produce low BABIP, but Ryan’s mark is likely due to the outfielder adjustments we’ve discussed — and he’ll lose some of that benefit as fly ball distance edges higher. Even so, if a fantasy manager in your league is concerned about the right-hander’s high fly ball rate, don’t hesitate to inquire about Ryan’s availability.

Justin Verlander, Houston Astros: The veteran’s ground ball rate has fluctuated over the years. Through his 10 starts of 2024, it was the lowest of his career — and the lowest among pitchers throwing at least 50 innings. Verlander’s 11.7% HR/FB mark is just a tick above league average, but the sheer number of fly balls leave him with the 11th-highest HR/9. Additionally, Verlander’s 14.2% K-BB% is his lowest since 2014 and is showing no indications of improvement. If Verlander continues this high fly ball pace once he returns from the 15-day IL (neck discomfort), he could do more harm than good over the second half.

Nick Pivetta, Boston Red Sox: Pivetta is a tough read since he sports an inordinately high HR/FB%, despite pitching a lot in Fenway Park which suppresses homers. Fenway Park is the second-best venue for runs (behind only Coors Field), but that’s due to the fact that the Green Monster turns outs into hits. It’s not because of homers.

He could just be in an unlucky stretch with regards to HR/FB, or he may deserve this higher level, and thus not be subject to second half-regression from his 16.2% HR/FB. If it’s the latter, that rate will grow higher as the ball flies further. OK, Pivetta’s career-low 6.4% walk rate is fueling a solid 20.9 % K-BB%. That’s encouraging, but adding even more home run risk to a guy already with the proclivity for the long ball? That’s not a great combination.

Andrew Abbott, Cincinnati Reds: To be honest, next level analysis isn’t needed to be concerned about Abbott as his 3.40 ERA is over a full run lower than the associated expected levels. His 85.0% LOB mark isn’t related to average fly ball distance and it’s hard to imagine that level of success continuing. However, Abbott’s .248 BABIP is artificially low, even for a fly ball pitcher. As such, the expected ERA correction could be even more severe.

However, there is another thing to consider here. The best way to mitigate regression is for skills to improve. It was just one game, and it was against a Red Sox lineup with a high strikeout rate, but in his last appearance, Abbott fanned a season-high 10 batters. Last year, Abbott punched out 26.1% of all hitters. This season, that number has slipped to 20.0%. It’s worth tracking Abbott’s next few outings and, if he continues to miss bats, he could be an intriguing buy-low option.

Hunter Greene, Reds: There is both a lot to like here — and a lot about which to be concerned. Greene hasn’t demonstrated it yet, but watching him pitch, it isn’t hard to envision more strikeouts and fewer walks in his future. That said, his current walk rate is high and he’s due some regression, regardless of the baseball.

Summer changes could serve to exacerbate his issues, though, especially if Green continues to issue excessive free passes. Hunter’s .252 BABIP and 7.8% HR/FB are both ripe for a correction, irrespective of the warning weather. Again, it’s easier said than done and Greene’s ceiling is higher than other pitchers we’re discussing, but a fly ball pitcher with a high walk rate is not a recipe for success in the Great American Ballpark.

Seth Lugo, Kansas City Royals: Lugo doesn’t meet the criteria of being a low ground ball pitcher (44.3%), but he has really been benefiting from the fly balls he does produce, so it’s worth a quick warning. His .267 BABIP is extremely low, as is his 8.1% HR/FB level. He sports a low 5.7% walk rate which helps, but his 20.8% strikeout rate is pedestrian and leaves him vulnerable to balls in play.

Lugo has been outpitching his peripherals to the point many feel he owns that skill. This is a slippery slope, though, and this kid of thought process often backfires. With Lugo, it’s not the volume of fly balls, but rather the extent of the dead ball benefits. He’s going to lose most of that in Kauffmann Stadium. Caveat emptor!