Summertime Sadness Coming for These Starting Pitchers?

There aren’t many refrains more common for fantasy sports writers than describing a hitter who is performing well during the summer as one who is “heating up with the weather.” 

And the thing is, more often than not, it is justified. Ballparks across the country become more hitter friendly as the weather heats up, and cold morning games and windswept, foggy night games become hot, humid oases for home runs. 

If you are skeptical of summer surges in offense, check out the last four seasons, with the months with the best SLG, OPS, ISO, and wOBA highlighted in red. You’ll notice that every year, the best marks are put up in July and August.

With that in mind, who are some of the pitchers with the most to lose this summer? And are there some with the skills to help them succeed against the odds?

Home runs are the quickest way for regression to bring early season results back down to earth, so we’ll start with some of this season’s starting pitchers who have allowed the fewest home runs. 

There are plenty of names with sub-0.80 HR/9 figures who are likely regression proof, or at least who are unlikely to fall out of ace status this summer. Jacob Misiorowski and the rest of the Cy Young contenders are more or less safe bets to keep putting up low ERAs. 

Gage Jump, despite pitching for the A’s, has elite fastball velocity and strikes out nearly a batter per inning, so he should continue to put up a solid ERA, though his current 2.04 ERA may drift up towards his 3.75 xFIP. 

But there are plenty here with question marks that could foreshadow bigger ERA jumps than Gage’s. 

The pitchers with yellow highlights in the above table represent those with at least two below average metrics, with an emphasis on high walk rates, low groundball rates, and low average fastball velocities. All of these characteristics make the potential, and increased likelihood, of allowing more summer long balls even more problematic.  

I’ll group these pitchers into two distinct categories of concern: high walk rates with low fastball velocities and low groundball rates with low fastball velocities. Spencer Arighetti falls into both categories, so I’ll discuss him amongst the high walk rate arms.

Of these five starters, David Peterson has certainly been the least relevant for fantasy managers thus far, with his 7.71 ERA as a part-time starter for the hapless Mets. However, a trade to the Cubs may have piqued some managers’ interest, as might his 3.84 xFIP, 9.16 K/9, and 55% groundball rate. 

The lefty did put up a strong first half last season, before crumbling down the stretch. Through July, the then-29-year-old had already compiled a career-high 121 innings with 101 strikeouts and a 0.52 HR/9, helping him to a 2.83 ERA and 3.66 xFIP. 

Over his final ten starts, Peterson’s ERA spiked to 7.74, despite his xFIP remaining steady at 3.88. His HR/9 jumped 24 points, his BB/9 jumped to 4.53, and his strand rate plummeted to 53.1%. Even as his strikeouts increased, he was unable to escape the bad luck and big inning. 

His profile is just as risky this year, he just hasn’t had as strong of results. Even with the change of scenery, he is a streamer at best in 12-teamers against less powerful offenses, especially if the conditions at Wrigley Field in the later summer happen to favor pitchers this season. But really, Peterson should only be considered in deeper leagues as a volume play. 

Landen Roupp has the best underlying numbers of this group, if not the best overall numbers thus far. The Giants starter has nearly a 10 K/9 thus far, with an xERA and xFIP nearly a full run lower than his 4.15 ERA. After breaking out last season, with a 3.80 ERA over 22 starts, Roupp has increased his strikeout rate and cut his home runs per nine nearly in half. 

Perhaps most impactfully for fantasy, these improved strikeout figures have come over an increased innings total per start. After averaging 4.8 innings per start last season, his first as a full-timer in the majors, Roupp is at 5.4 innings per start this season, which has helped slightly pull up his quality start rate from 36% last season to 40% so far in 2026. 

Roupp’s sinker, curveball, and changeup all are posting increased run values this season, he’s generating more chase, and his Pitching+ has jumped from 102 up to 107. 

The Giants have a 97 park factor over the last three years, and just a 91 HR park factor, both overall and for left-handed batters, though Roupp largely eschews platoon splits. 

Out of this group, Roupp should be the best bet to avoid regression and should be target to add or buy in 12- and 15-team leagues.

A breakout in 2025, Kris Bubic has battled injuries since the end of last season. He is on rehab assignment this week, as he uncorked his signature breaking ball for a strikeout at AAA Omaha on Wednesday.

The 28-year-old lefty has made just nine starts this season, with a 4.11 ERA across 50.1 innings. He is striking out more than a batter per inning, which is in line with the 8.97 K/9 he put up last season, but his BB/9 has risen from 3.02 to 4.65. 

Put simply, he earned some leeway based on his performance last season, but this may be closer to his true talent level, compared to the 2.55 ERA he finished with last season. This season, he’s allowed more home runs and walked more batters, while stranding fewer baserunners and getting less groundballs. 

He should be considered in a similar tier as Roupp, a high-threes ERA arm with solid strikeout numbers and an unspectacular WHIP, assuming he comes back healthy in the next few weeks. 

Martín Pérez is likely not fooling many managers. At 35-years-old, his 3.00 ERA would be the second best mark of his 15-year career. 

For Atlanta this season, the veteran lefty has walked the tight rope of a low-strikeout, high-walk arm by running a 6.5% barrel rate, according to Statcast. While he was above 15% last season, 2025 was the only season where Pérez had a barrel rate above 10%. 

But for his career, Pérez has allowed a 5.42 ERA and .297/.364/.474 slash against him in July. This could be a great time to throw him into a trade, if possible. 

The more likely scenario is being ready to cut bait if and when more exciting young arms begin entering the pool as teams call up hurlers to help them through the summer. For the Braves, this could even mean the rehabbing duo of Hurston Waldrep and AJ Smith-Shawver, both of whom I covered last week.

Spencer Arrighetti is the most concerning of this group, at least in terms of having perhaps the most room to regress away from the early season success he’s enjoyed so far. 

The 26-year-old was a popular breakout candidate heading into drafts last season after putting up a 10.61 K/9 in 2024 as a rookie for the Astros. Injuries limited him to just seven starts last season, and he shook off the rust to begin 2026, racking up 7 wins in 12 starts with a 3.13 ERA and 8.87 K/9.

But the lack of home runs allowed this season does not match his career track record, which is admittedly limited. His above average 0.78 HR/9 this season compares quite favorably to his 1.30 HR/9 as a rookie. 

Arrighetti’s FIP and xFIP are both higher this season than they were in 2024, despite the nearly 1.5 run difference in ERA. The strikeouts have diminished, his average fastball velocity has dipped nearly 2 mph, the walks have increased, and the strand rate has jumped by about eight points, pointing to what could amount to a spell of good luck for Arrighetti. 

Is there anything he’s doing better that could help him avoid a summer surge in homers?

While his fastball velocity has diminished, so has his fastball usage, as he’s opted for the increasingly popular approach of mixing a fastball, cutter, and sinker, the latter of which was not in his arsenal in 2024. Arrighetti is also throwing his slider and curveball more in 2026. All of this seems to be helping him avoid home runs and hard hit balls in general, as his hard hit rate has dropped from 39.8% in 2024 to 30.8% this season. 

Arrighetti does not have as forgiving a home park as Roupp or Bubic in terms of home runs, something that showed up in earnest in his last start, where he allowed three home runs pitching at home against the low-powered Guardians. He also struck out eight. 

If you have an opportunity to sell high on Arighetti, who still has some hype from his strong strikeout performances as a rookie, now is absolutely the time to do so. I would expect his eRA to finish well above the 3.13 mark it sits at today. And projection systems seem to agree, all placing him between a 4.23 and 5.00 ERA for the rest of the season. 

If you hold, just know that any potential strikeouts carry potential heavy ERA and WHIP risk. 

Now for the pitchers with low groundball rates and low fastball velocities. 

Ranger Suarez has done this enough times to earn the benefit of the doubt. But so far pitching with the Red Sox, Suarez has actually been even better than his full season lines with the Phillies in 2024 and 2025, with a 2.83 ERA and 9.15 K/9 so far. He has not bested either of those marks since becoming a full time starting pitcher in 2022. 

Suarez is pitching a bit differently as well, or at least is getting to his strong results in a different way, as his HR/9 is around 40 points lower than it has been since 2024 and his usually high groundball rate is below 40% for the first time in his career, even as his barrel and hard hit rates are both in line with career norms. 

All three of his fastball varieties are performing better this season with positive pitch values, while his changeup, one of his best offerings last season, is a negative pitch value offering this season. 

Suarez does have a history of things falling apart in the second half, even as he has one of the most sterling postseason records in recent memory. For his career, he has a 15.8% K-BB%, a .228 batting average against and 1.15 WHIP in the first half. All of these figures slide in the second half, where he has put up a 13.6% K-BB%, a .272 batting average against, and 1.39 WHIP. 

If the name brand of Suarez makes him interesting to opposing managers, now is a perfect time to explore a trade of the veteran lefty, especially in shallow Roto leagues, where an increase in WHIP would be especially painful given his volume. 

Michael Soroka’s 3.07 ERA would be far and away his best since his dominant 2019 rookie season. The 28-year-old is thriving with the Diamondbacks so far, building on a comeback last season by shaving walks and home runs off of his line. 

He seems to be exhibiting far better command, which would back up the storyline that last season was about regaining some of his signature feel after multiple seasons in the pitching wilderness on his way back from injuries. 

This season, his Location+ is up 10 points to 107, he is throwing a first pitch strike 64.6% of the time, compared to 58.8% last season, and is avoiding the heart of the zone to the tune of a 25.6% H-Zone% this season, compared to a 30.9% mark last season. 

Soroka is currently on the IL with a strained left glute. Considering his injury history, this may give some managers pause, but given that his injury is not in his lower legs or shoulder, he should bounce back. Consider him a buy low in most formats. 

And to round things out, the veteran Seth Lugo. Master of the deep arsenal, Lugo is throwing five pitches 15% of the time or more this season, and has bounced back from a lackluster 2025 to contribute a 3.69 ERA and nine quality starts across 15 starts this season. 

His strikeout rate has fallen precipitously since his time starting with the Padres though, and is below 7 K/9 this season. After running a 15.4% HR/FB% last season, this year’s 6.6% feels like a bit of a mirage, especially considering his 5.21 xERA and 42.4% hard hit rate. 

Outside of deep leagues, the brand name value of Lugo may allow you to eke out a bit of value here via trade. At the very least, he can be a streamer in shallow leagues, though like Arighetti and Suarez, there is considerable ratio risk here given the volume he is likely to provide.