The baseball community generally adheres to the same philosophy for evaluating pitchers based on one or two spring training appearances: don't do it. Performance can certainly offer intrigue though, and relievers Johnny Barbato and Chasen Shreve have provided a reason to be excited about their potential in the Yankees bullpen, especially due to their unique circumstances.
In 2014, reliever Shawn Kelley famously showed up to the stadium one day in a horse mask, looking like a real-life Scooby-Doo villain. With David Robertson entering the season as the closer, Kelley was supposed to take over the setup role, and he would've gotten away with it too, if it weren't for the meddling Dellin Betances. After the season, he was traded for Johnny Barbato, a right-handed relief prospect in the Padres organization.
Barbato spent the 2015 season between Double-A and Triple-A. He's subsequently kicked off spring training with four strikeouts and no walks in two games. While 2.1 scoreless is nothing to be excited about in the long run, his radar gun readings are. According to YES Network, he has hit 96 mph with his fastball and mixed in a couple of mid-90's two-seam fastballs, featuring late horizontal movement. A lot of pitchers add velocity during the course of the season, so a further spike in velo may be in the cards for the 23-year-old.
The truly exciting thing about Barbato lighting up the radar gun is that when he was acquired, he was coming off an elbow injury that could have needed Tommy John surgery. Last season, he threw 67.1 innings over 40 appearances, so his elbow was probably in decent shape if they let him throw that much. The fact that he is already sitting in the mid-90's will hopefully be the nail in the coffin of his elbow concerns. If he reaches the upper 90's with the same late life he has displayed so far, he could be a mainstay in the Yankees bullpen for years to come, not just in 2016.
Chasen Shreve has also gotten off to a good start. He actually threw his one and only inning yesterday against the Red Sox, retiring the side on five pitches with one strikeout. He struck out Red Sox outfield prospect Bryce Brentz with his split-change, a pitch he used to neutralize righties throughout the 2015 season.
After looking like an elite reliever for most of the season, Shreve imploded in September. He allowed more walks than strikeouts and pitched to a 13.50 ERA in six innings over ten appearances. According to Ryan Hatch at NJ.com, catcher Brian McCann thought he may have been tipping his pitches towards the end of the season, while Larry Rothschild suggested that he simply ran out of steam.
Ordinarily, one scoreless inning would not mean anything for a pitcher, but looking back to September, Shreve literally only had one good outing. Almost invariably, hitters were getting to Shreve, assuming he actually threw the ball in the strike zone. Considering how effective he was through August, even a few disaster-free outings from Shreve suggest that his September performance was a fluke.
Other relief prospects like Nick Rumbelow, James Pazos, and even veterans like Kirby Yates and Vinnie Pestano still have plenty of time to prove themselves during spring training. One thing is for certain though: the Yankees bullpen has the chance to be much more than just Betances, Miller, and Chapman.