The early stages of any major league season are rife with unexpected performances — be they unexpectedly good or unexpectedly bad — that leave many fans and onlookers wondering whether an April change in production is the beginning of a trend or simply some small-sample noise that’ll even out over a larger slate of plate appearances or innings pitched. Sifting through what’s real and what’s likelier to be smoke and mirrors is both one of the most exciting and also most frustrating elements of the season’s first couple months.

This, as with most everything in baseball, is an inexact science. Teams spend millions to build out data and analytics departments that can develop predictive models in an effort to more accurately quantify these things. Sites like FanGraphs, Baseball Prospectus, PitcherList, Baseball America and countless others offer heaps of publicly available data that allow those of us on the outside looking in to throw our own hats into the ring as we attempt to decipher whose ostensible breakouts are going to hold up … and who’ll come back down to Earth.

MLBTR’s Darragh McDonald took a look last week at Jose Soriano‘s in-progress breakout in Anaheim — a huge development for the Halos that could have a broad range of implications. Readers are encouraged to check that out in full, but here are six more arms (plus a couple “honorable mentions,” of sorts) whose 2026 strides have piqued my interest. Obviously, this isn’t a comprehensive list of every possible breakout arm in the sport, but the arrows here are pointing up. (Players are listed alphabetically, not ranked.)

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