Starting Pitcher Fantasy Baseball Risers - K-BB% Analysis and 2025 Draft Targets

January 25, 2025

Jarod's starting pitcher fantasy baseball sleepers and risers with increased K-BB% year over year. These are SP fantasy baseball draft targets for 2025 drafts.

If you're here reading this article, you're likely leaving no stone unturned in your pursuit of finding players who will not only help your fantasy team but also return value by outperforming their ADP. Last season, I wrote this article, and the biggest riser was Tarik Skubal; not only did he outperform his ADP, he was the eventual AL Cy Young winner.

Does No. 1 on this year's list, or any other covered here, have that potential? Before we dig in, if you're unsure why we're looking at K-BB%, then read this article by our very own Nick Mariano. To summarize, when viewing pitchers through this lens rather than K/9, for example, we're focusing more on what pitchers can control, rather than a generic stat like ERA.

As always, don't use stats in a vacuum, and instead use them to complete a well-rounded view. Also, note that for this exercise, only starting pitchers with a minimum of 50 innings pitched were used as the universe of players analyzed. Let's see who had the biggest changes in K-BB% from 2023 to 2024.

Jack Flaherty, Detroit Tigers

+11.4 percent rise in K-BB%

With a 4.99 ERA, 1.58 WHIP, and a 12.6 percent K-BB%, perhaps the most positive takeaway from Jack Flaherty's 2023 campaign was that he was able to pitch 144 1/3 innings throughout the season.

The 6-foot-4 hurler tossed 104 1/3 innings combined between 2021 and 2022 after multiple shoulder-related injuries and an oblique strain caused him to miss time, so to finish with that many IP in 2023 was a win.

The 2024 season, though, gave us a glimpse into the past, as Flaherty more closely resembled the player we saw in 2019 who placed fourth in NL Cy Young voting.

The righty posted a 3.17 ERA and 1.07 WHIP and saw his K-BB% rise 11.4 percent, the most for any pitcher who logged more than 50 innings pitched, going from 12.6 percent to 24.0 percent. It was a result of a drastic increase in K%, from 22.8 percent to 29.9 percent, while significantly reducing his BB% from 10.2 percent to 5.9 percent.

So, how was he able to improve so much? Well, if you check out his Baseball Savant page, you'll see that one of the changes made from year to year was the elimination of the cutter, increasing the usage of the slider, curveball, and fastball.

What stands out the most, however, is right at the top of the page, showing that the veteran's Breaking Run Value went from the 16th percentile (left) to the 98th percentile in 2024 (right).

So, we dig deeper and find that while the run value (RV) on the slider and fastball both increased, it shot up the most on the curve, from an RV of 1 to an RV of 12. A 12 RV for a curveball was second only to Arizona's Zac Gallen.

Not much stands out as far as change in the horizontal and vertical movement for the pitch, but what is noticeable is that he was throwing it 1.2 mph faster than the year before. Whiff% went from 40.2 percent to 43.6 percent, but it also seems that it has helped play off the slider and vice versa. Whiff% on the slider went from 26.6 percent to 36.3 percent.

Jack Flaherty had a 70.6% whiff rate on his knuckle curve last night (17 swings, 12 misses).

The 12 swings and misses on his knuckle curve are a single game high for Flaherty. https://t.co/QObps9w5Mx

— Mathew Brownstein (@MBrownstein89) October 26, 2024

Now, the question is whether it is sustainable. The problem is that those stats are looking at the season as a whole, and if you get more granular, you'll see that velocity on all pitches dipped across the board once Flaherty became a Dodger in August.

From September 15 through the end of the season, a stretch of eight starts (including the postseason), the righty allowed 28 earned runs in 36 innings (7.00 ERA) with an 18:29 BB:K (11.1 percent BB%, 17.9 percent K%).

With the drop in velocity and late-season ineffectiveness, one could surmise that his arm/shoulder was fatigued after not throwing that many innings since 2019. This could also be partly why he's still a free agent at the time of this writing.

Be that as it may, with a 3.48 FIP and a 3.00 SIERA straddling his 3.17 ERA, it's hard to insist that regression is due in 2025. Keep an eye on his fastball velocity in the spring, and if it is 93.0 or lower like it was with the Dodgers, then perhaps fade him if you haven't already drafted.

If it is higher, then take a chance. If he comes out of the gates hot, potentially use him in a trade later in the year. He's still only 29 years old, and the former first-round draft pick should have some useful years ahead of him, but he doesn't look like this year's Tarik Skubal.

Sonny Gray, St. Louis Cardinals

+7.4 percent rise in K-BB%

Coming off a 2023 season in which he came in second in AL Cy Young voting, Sonny Gray was going to be hard-pressed to perform better than that in 2024. Yet, in many ways, Gray improved year over year even though things like ERA, WAR, and Cy Young votes did not show it.

The righty set career bests in BB% (5.8 percent), SwStr% (13.4 percent), and K/9 (10.98). Despite pitching 17 2/3 fewer innings in 2024 than he had in 2023, the veteran tallied 20 more strikeouts than he had the previous year, finishing with the ninth most in the entire league (203).

The improved command and strikeout rate is what landed him on this list, with a 24.4 percent K-BB%, which was a career-best by far with 19.6 percent in the shortened 2020 season being the prior high-water mark.

What made him so successful in St. Louis then?

Well, looking at his pitch mix from season to season, nothing jumps out except the apparent deemphasis on the curveball in favor of the cutter (see above chart). Looking at velocity and movement changes, we don't see much there, either.

When dissecting the pitch mix by batter handedness, however, we do see some interesting changes. On the chart below (left), it appears Gray has greatly increased the number of times he'll throw a cutter to righties over the last couple of years, but surprisingly at the cost of the sweeper.

The three-time All-Star's sweeper is his signature pitch, so to see the usage drop against righties is intriguing. What may be even more eye-opening is how he's increased its use against lefties (right), which sounds counterintuitive.

In 2024, Gray recorded a 40.6 percent Whiff% on the sweeper to lefties, so it was working in that situation and must have been by design.

Sonny Gray is a unicorn when it comes to sweeper usage vs. lefties. 57% of his two-strike pitches to LHB are sweepers and he has an elite 36% whiff rate against them pic.twitter.com/jsSyluugjm

— nate schwartz (@_nateschwartz) June 13, 2024

As mentioned earlier, Gray is known for his sweeper. It had a run value of 19 in 2023, the best in all of baseball by far. Although it dipped to an RV of 5 in 2024, Pitching+ on the sweeper came in at 125 in 2024, which was tops amongst pitchers with at least more than 5 percent usage (it graded at 121 in 2023).

The two metrics that go into Pitching+, Location+ and Stuff+, came in at 114 and 152, respectively, both second-best in baseball. So, he was throwing the sweeper how he intended it and it was going where he wanted it to go in the particular situations in which he used it (i.e. 2-0 count vs. 1-2 count).

This all points to a repeatable process that can be replicated in 2025, and with a FIP (3.12), xFIP (2.82), and SIERA (3.03) much lower than ERA, there's reason to believe the 35-year-old can tidy up last year's 3.84 ERA using this approach. A 14.3 percent HR/FB% could be a limiting factor to that, though.

Being 35 years old, however, managers who draft the 2011 first-round draft pick should keep an eye out for any indications of age-related decline such as a dip in velocity. But don't expect him to fall off a cliff, and he's been quite durable, having made at least 22 starts in each season since 2014 (excluding 2020).

He's likely a long shot for the Cy Young with all the young arms in the NL (i.e. Roki Sasaki, Paul Skenes, Spencer Strider, to name a few), but if he can post similar stats to last season with an improved ERA, he could certainly put himself in the conversation.

Carlos Rodon, New York Yankees

+6.2 percent rise in K-BB%

After missing half of the 2023 season with an injury, Carlos Rodon never looked quite right even when he returned to the mound in July of that season, finishing with a 6.85 ERA, 1.45 WHIP, and a 12.6 percent K-BB% over 14 starts.

The southpaw relied heavily on his four-seam fastball, throwing it 60.4 percent of the time, which had worked for him in 2021 and 2022. With his fastball/slider combination accounting for nearly 90 percent of his pitch mix, it seemed hitters knew what to expect.

Needing to bounce back in a big way in 2024, the two-time All-Star altered his pitch mix, which appeared to help him improve statistically year over year.

The veteran hurler dropped the usage on the four-seamer by 11.0 percent, down to 49.4 percent, increased the usage on the changeup from 4.3 percent to 12.9 percent, and added a cutter that he threw 3.5 percent of the time.

However, that was only a piece of the puzzle. Looking at year-over-year changes, not a whole lot stands out other than a noticeable change in Whiff% on his changeup, from 42.1 percent to 49.5 percent (+7.4 percent). Per Baseball Savant, his offspeed offering went from a 52nd-percentile RV to the 90th percentile.

Honing in on the changeup, Stuff+ on the pitch went from an 84 in 2023 (and no higher than 98 in any other season since 2020) to 129 in 2024, which was fourth-best in all of baseball.

Looking for movement changes for the changeup, the vertical drop on the pitch has increased remarkably relative to his other pitches over the last few years, but more so from 2022 with the Giants to 2023 with the Yankees, as seen below.

So, what happened? Well, the pitcher has said that the grip on the pitch was adjusted when he came to the Yankees, and last season, he perfected it which led to increased effectiveness.

Carlos Rodón, Changeup Release (slow) pic.twitter.com/8EncWT3wZS

— Rob Friedman (@PitchingNinja) July 29, 2024

The lefty posted a 3.96 ERA, 1.22 WHIP, and an 18.8 percent K-BB%. A SIERA of 3.78 and a BABIP of .284, in line with career norms, appear to reinforce that the improvements were not a fluke. Making it through the season fully healthy was the cherry on top of the rebound.

The 32-year-old still had a worrisome HR/FB% (13.4 percent), which will probably limit too much more of an improvement in ERA; however, Rodon's return to a high K% pitcher should be something managers can count on in 2025, while playing for the Yankees should ensure another 10-plus-win season.

K-BB% Riser Honorable Mentions

• Ryan Weathers  +10.1 percent  (Update: Weather is dealing with a forearm strain that will put him on the IL to begin the season)
• Tylor Megill  +9.4 percent
• Ryne Nelson  +7.3 percent
• Trevor Williams  +7.0 percent

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