Starting Pitcher Rookie Check In: Bubba Chandler, Parker Messick, and Nolan McLean

We have covered several hitters for our rookie check-ins. Though we will cover more in the future, we wanted to shift our attention to three starting pitchers worth highlighting that were rookie-eligible heading into the 2026 fantasy baseball season. Several rookies have been performing well, with some struggles. We’ll continue examining rookies throughout the season, including some advice on whether to buy, sell, or hold in keeper and dynasty formats.

Bubba Chandler, SP, Pirates

Paul Skenes probably gave us unrealistic expectations for Bubba Chandler or another top Pirates’ pitching prospect. On the FanGraphs Top 100 Prospects, Chandler was No. 10 as the fourth starting pitcher behind Nolan McLean (No. 3), Trey Yesavage (No. 8), and Thomas White (No. 9). Prospect evaluators highlighted his electric fastball and a changeup with a 70 future grade. The prospect reports, however, mentioned Chandler’s command issues.

When a player performs below expectations, one of the first things to look at is how “unlucky” they have been. But Chandler has a low BABIP (.257) and while he has struggled to strand runners (67% left on base rate), that number is up from 2025 (61.6%). Luck factors have shifted more favorably for him, yet the skills plummeted. 

Sure enough, Chandler has been struggling with control, though he also isn’t getting the whiffs we might expect. Both his ball rate ‘(37% this year after 34% last) and his swing strike rate (10.3% vs. 13.4%) have moved the wrong direction in 2026. Chandler went from a 21.8% K-BB% in 2025 to a single-digit K-BB% (6.8%) in 2026.

Both that electric fastball and the highly regarded changeup are getting fewer swinging strikes in 2026 (9.3% and 12.3%, respectively) vs. 2025 (14.1% and 17.3%).  We have seen Chandler’s slider increase from a 9.9% swinging-strike rate (2025) to 13.5% in 2026, but that’s still three percentage points below the league average swinging-strike rate for a slider. The next questions is why the fewer whiffs. 

Before we dive into what’s up with the fastball and change, we should note that he started throwing a sweeper and sinker in 2026. New, ineffective pitches could be the culprit here, but that doesn’t seem to be the case. The sweeper gives Chandler a variation of his slider, with more drop (3+ inches) and glove-side sweep (7 inches), and it is working well as a weapon vs. righties (.236 wOBA, .227 xwOBA).

The sinker is also primarily used against right-handed hitters, though he still only throws it 9.2% of the time. It does the job a sinker is meant to do, generating an 80% groundball rate, leading to a .281 wOBA from RH bats. It does have a .348 xwOBA, so it may eventually have less success.

But given the expectations for the four-seam and change, and the fact that they make up more than 70% of his arsenal, that is probably where we want to look for his issues. Interestingly, Chandler’s four-seamer added one inch of induced vertical break, yet it lost two inches of arm-side fade, suggesting he has been cutting his four-seamer more in 2026. That’s partly explained by Chandler raising his arm angle by six degrees in 2026. Chandler’s vertical release point hardly shifted (under 0.5 inches). Yet, his horizontal release came over two inches (2.4) closer to his midline, leading to a higher arm angle, as seen below. That seems to have impacted his four-seam pitch shapes.

Theoretically, Chandler’s four-seam should generate whiffs and weak contact with the near-elite level of induced vertical break, but the heater might be more hittable if he cuts it more toward the middle of the plate. But we already noted the decrease in whiffs, and the pitch is getting crushed by both right-handed hitters (.349 wOBA, .362 xwOBA) and lefties (.357 wOBA, .397 xwOBA). Gas like Chandler’s should be more effective, but that is only true if he is locating.

The visual below shows Chandler’s four-seam heatmaps over the past two seasons.

You can see Chandler’s four-seam used to sit right at the top of the zone, where batters might have trouble going up and getting 98+. This year, it is sitting middle-middle.

Chandler’s changeup, meanwhile, has been deadly against right-handed hitters, allowing a .167 wOBA (.192 xwOBA) and generating a 22% swinging-strike rate in 2026, though he only throws it 9% of the time. Meanwhile, the results against Chandler’s changeup against left-handed hitters have been worse (.289 wOBA, .297 xwOBA) with a 10.1% swinging-strike rate in 2026. For context, Chandler’s changeup allowed a .118 wOBA (.162 xwOBA) and an 18.5% swinging-strike rate in 2025 against left-handed hitters. Since Chandler’s changeup results and whiffs changed, we might speculate on the locations.

The visual below shows Chandler’s changeup heatmaps against right-handed hitters in 2025 and 2026.

Again, Chandler’s location has shifted drastically. Specifically, his changeup is 6.1 inches lower in the zone and 5.8 inches closer to the middle of the plate in 2026 vs. 2025. Chandler’s changeup Location+ increased to 104 (2026) from 98 (2025), though we’re dealing with a small sample and that location doesn’t look ideal.

All of Chandler’s expected ERA metrics suggest he is terrible, several with numbers over 5.00. However, Chandler possesses multiple pitches with above-average stuff grades while boasting average command. It looks like he might need to make some adjustments on his locations – that might take time and presents a buying opportunity in redraft, keeper, and dynasty formats. 

Nolan McLean, SP, Mets

Before Nolan McLean’s past two outings, he was one of the best rookie starting pitchers in 2026. In his first nine starts, McLean allowed 17 earned runs and four home runs, supported by a high-end 24.1% K-BB%. Then he allowed 13 earned runs with four home runs in just two starts against the Reds and Nationals. McLean allowed a .265 BABIP and stranded 71.7% of runners in those first nine outings, but that turned in his two most recent starts (.333 BABIP and 32.5% strand rate). 

Even in his good stretch, McLean had just a 9.8% swinging-strike rate, which seems low given his stuff grades (107 Stuff+). McLean’s curveball was nearly six points above the league average, with the changeup generating swinging strikes two percentage points more than the league norm. Unsurprisingly, McLean’s curveball and changeup possess above-average movement profiles, typically aligning with high stuff grades. That’s evident in McLean’s 126 Stuff+ via the curveball and a 103 Stuff+ from the changeup.

As a pitcher who boasts high-end stuff, we love that McLean uses a deep arsenal of 3-4 pitches thrown at double-digit percentages against either side of the plate. Against right-handed hitters, McLean has been throwing more sinkers (46%) and fewer sweepers (20.9%) in 2026 vs. 2025 (36% sinkers and 32.3% sweepers). 

Interestingly, McLean’s sinker hasn’t been generating as many ground balls and weak contact against right-handed hitters, like in 2025. That’s evident in McLean’s .299 wOBA (.271 xwOBA) and six-degree launch angle in 2026 compared to a .206 wOBA (.257 xwOBA) and a -15-degree launch angle in 2025 against righties. As seen in the heat maps below, McLean has been throwing his sinker over one inch higher in the zone, a half-inch more toward his arm side. Since the Location+ numbers haven’t shifted much via the sinker, there’s a chance his groundball rates shift somewhat between his 2025 and 2026 numbers.

The visual below shows McLean’s sinker heatmaps against righties in 2025 and 2026.

McLean throws six pitches 10% of the time or more against left-handed hitters in 2025 and 2026. He started throwing more sinkers (29.2%) and four-seamers (21.7%) to lefites in 2026 vs. 2025, while lowering his sweeper usage (13.5%).

The visual below shows McLean’s sinker heatmaps against lefties in 2025 and 2026.

Throwing  more four-seamers against lefties may not be helping him, because his four-seamer has been crushed, giving up a .425 wOBA (.503 xwOBA) to left-handed hitters. It’s worth highlighting that McLean’s sinker and four-samer both added nearly two inches of arm-side run in 2026, while the sinker lost three inches of downward movement (25.3 inches). Theoretically, McLean’s sinker and four-seamer could confuse hitters with similar induced movement profiles, leading to opposing hitters guessing at the fastball type. 

Among qualified starting pitchers, McLean ranked 12th in Stuff+ and 43rd in Location+, making one of the few players with a high-end stuff grade and above-average command. We should probably expect more whiffs from McLean’s arsenal, but there’s a deep arsenal with good stuff and command within his profile. If these last two starts have made another manager anxious, I would be inquiring about buying on McLean. 

Parker Messick, SP, Guardians

After nearly 40 quality innings in his debut, Parker Messick is showing us that 2025 wasn’t a fluke. Messick has maintained his 19.4% K-BB% in 2025 into 2026 (20.4% K-BB%), despite a higher ball rate (36%) and no gains in swinging-strike rate (11.7%). 

He has been fortunate in 2026, with a .273 BABIP and 85.6% strand rate. Messick’s BABIP is lower than the one from 2025 (.359), though he had a similar strand rate. As a prospect, Messick’s changeup was graded as his best pitch (60 Grade). We’ve seen that so far, with the change eliciting a 25% swinging-strike rate in 2026. That’s up from a 15.8% swinging-strike rate in 2025. 

Against right-handed hitters, Messick throws his changeup (29.6%) and four-seamer (29.3%) most often, with three other pitches thrown over 10% of the time: the sinker (13.5%), curveball (12.4%), and cutter (12.4%). Besides the cutter, Messick’s four other primary pitches allowed a wOBA under .300, with the changeup and four-seamer having even better expected metrics.

The visual below shows Messick’s changeup heatmaps against righties in 2025 and 2026.

Messick consistently located his changeups low and away from right-handed hitters in 2025 and 2026. He has been throwing his changeup more often in the areas low and below the zone in 2026, leading to opposing hitters chasing more. Messick is throwing his changeup in the zone 29.2% of the time with a 46.5% chase rate in 2026. For context, Messick’s changeup zone rate was at 34.9% with an above-average 36.8% chase rate in 2025. Messick consistently commands his changeup, further supported by his 103 Location+. 

The new pitch Messick has been throwing in 2026 is the cutter, seen in the visual above. Messick’s cutter has been blasted, allowing a .487 wOBA against right-handed hitters, though the .349 expected wOBA suggests better potential results. The cutter gives Messick a harder version of his slider, with a similar induced movement profile. Messick’s cutter moves somewhat between his four-seam and slider. Messick’s cutter and slider often have been thrown toward the inside of the plate against right-handed hitters. 

The visual below shows Messick’s cutter and slider heatmaps against righties in 2026.

Messick’s cutter has been located 5.5 inches above the slider and more than two inches further towards the inside of the plate, which makes sense given the higher velocity and different movement profile. Unfortunately, when Messick throws his cutter in the zone against right-handed hitters, they crush it, to the tune of a .997 wOBA and .537 xwOBA. It seems like the cutter tends to be a pitch-to-contact offering, allowing a 82.9% contact rate. Messick might want to adjust his cutter usage and locations, especially since opposing right-handed hitters hit the cutter hard.

Messick is finding success as a pitcher that relies more on command (106 Location+) than stuff (96 Stuff+). A couple of weeks ago, Michael Baumann dove deep on the unconventional was Messick is doing this. His skills have been above-average, evidenced by his K-BB%, command, and ability to generate whiffs. There will be some regression in the ratios because he remains fortunate with his BABIP and strand rates. However, Messick is a case where we want to trust the skills, and potentially buy high on him in keeper and dynasty formats.