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The concept of a “best” pitch is more subjective than anything. Obviously results play a major part in it, but how much should peripherals be weighed, whether it’s velocity, spin or whiff rates? Or is it just the pitch someone goes to when their back is up against the wall and they need an out?

Run Value is a good tool to help measure this, taking a pitch’s results into consideration but also the context. Getting an out with the bases loaded is inherently more valuable than one with nobody on base, so it weighs that pitch with more perceived run value.

So who has the best pitch on staff? Let’s take a look at which Pirates have the best run value by pitch.

Four-seam fastball: Mitch Keller -- 9 Run Value, .257 batting average, 24% whiff rate, 40% hard-hit rate

Keller definitely has a full arsenal and hasn’t been afraid to add new pitches the past few years, whether it’s a sinker or a sweeper. The four-seamer is ol’ reliable, though, and whenever he is clicking, he’s able to pitch off of it with his offspeed and breaking offerings.

Sinker: Paul Skenes -- 18 RV, .184 BA, 29.3% whiff rate, 35.5% hard-hit rate

Perhaps this is cheating a bit since this isn’t a “true” sinker. Skenes’ “splinker” is a sinker-splitter hybrid that offers an elite combination of velocity (94 mph) and drop (30.3 inches of vertical movement). It may be a hybrid, but he views it as a sinker first and it certainly was effective.

Cutter: Luis Ortiz -- 6 RV, .273 BA, 16.8% whiff rate, 34.7% hard-hit rate

Ortiz has a power fastball and slider, but he struggled in 2023 in part because he couldn’t develop a changeup. In April, he and pitching coach Oscar Marin decided to shift their focus to developing a cutter instead, and it effectively became the offspeed pitch he never had.

“Every time I go out there for my throwing program or when I get out there on the bump I work on it, because it's been huge for me, especially against lefties," Ortiz said in July, via interpreter and coach Stephen Morales.

Curveball: Joey Wentz -- 3 RV, .143 BA, 33.8% whiff rate, 21.1% hard-hit rate

A bit of a surprise here, Wentz was a September waiver claim and only threw 12 innings with the Pirates, but if you include his time with the Tigers, he can boast some impressive curveball results. Upping this pitch’s usage could give him a boost in 2025, as he only threw it 12.4 percent of the time and more against right-handers than lefties.

Slider: Hunter Stratton -- 6 RV, .100 BA, 43.5% whiff rate, 5.6% hard-hit rate

The Pirates have some really good sliders on staff (Jared Jones and Dennis Santana were in the running here), but Stratton’s was the most effective. A lot of that has to do with his cutter, which has a similar flight path before the slider takes off for another 6.4 inches of run (2.9 for cutter, 9.3 for slider).

Sweeper: Colin Holderman -- 8 RV, .165 BA, 39.3% whiff rate, 28.8% hard-hit rate

Holderman admits he doesn’t know who exactly taught him his sweeper, but it has turned into his best pitch. When it’s at its best, it’s playing off of his cutter’s movement while offering a change in velocity from his sinker. The only issue seems to be can he keep it consistent throughout an entire season, because when his wrist flares up, the pitch usually suffers.

Changeup: Skenes -- 2 RV, .088 BA, 54.8% whiff rate, 7.1% hard-hit rate

It’s no surprise that Skenes had multiple entries on this list, but the changeup may not have been the first guess since he can hit triple digits and get plenty of movement with his spin pitches. But Skenes also does a good job dropping changeups at the knees on his glove side, giving him another weapon for lefties.

“It kind of reminds me of, when I was young, catching Kevin Gausman,” said Joey Bart in September about Skenes’ changeup. “He would kind of tunnel that splitter to the changeup, and it's pretty devastating. So, he's got 100 mph and he's got plenty of offerings to get him in the zone and put guys away.”