This was late March 2012, and late March is a slog in baseball. Spring training has lasted too long, and still the season remains tantalizingly close, yet not quite here.

Will Kuntz, who was running the Yankees’ pro scouting department at the time, was in Bradenton, Florida, to do more self-scouting of the system. Within the slog there is, perhaps, nothing, um, sloggier than this. The Yankees were not overly blessed with prospects, and a scout could go days, weeks (months?) without seeing something that even could excite the imagination.

Kuntz remembers thinking, in his first trip to Pirate City, that the luxurious training facility was going to be the most memorable thing he laid eyes upon. Then the Yanks sent out a kid Kuntz had never heard of, who couldn’t be more than 5-foot-11 in spikes on the mound, and the initial thought is: “More of the same.” The kid is throwing his warm-up pitches, to Kuntz’s first thoughts, at about 80 percent. But with that same easy motion, the pitcher throws his first game pitch. Kuntz lifts his radar gun and it is 95 mph painted on the outside corner.

At that moment, Kuntz turns to the Pirates kid pitcher charting the game from the stands and asks what his radar reading was, not believing his own. He is told 95, still doesn’t believe it and quickly turns his gun off and on to reboot. Boom, the next pitch is 94 on the inside corner and the next is 95, and the Pirates farmhand hitter starts early and barely fouls the ball off.

Kuntz actually begins to wonder if he had imbibed too much the previous night, considers if this is an illusion somehow. He doesn’t even know who the damn pitcher is and he is wearing a Yankees uniform.

At 56 feet, the next pitch takes a hard turn left into the catcher’s mitt. “Absurd” is the word that ricochets through Kuntz’s brain. The hitter, expecting propane again, swings and misses. Either way, the at-bat was over since the pitch had cut over the plate and would have been a called strike.

“I’m not one to get excited about one at-bat, but this was such a special combo of arm strength, ease of delivery, fastball command and quality to the breaking ball that there was no other appropriate response,” Kuntz remembers vividly more than two years later. “I’d seen two plus pitches with command … from a Yankee prospect.”

Of course, Kuntz wanted to see more and did: The fastball was spotted in the mid-90s, the slider verged on unhittable and even the changeup was at least solid. But it was actually the next inning that turned Kuntz into a cheerleader.

A runner got on and from the stretch, the pitcher was slide-stepping and getting the ball to the plate in between 1.05 and 1.15 seconds, which is very quick. Yet the velocity and the command were unchanged. This was a young prospect.

He was supposed to lose one or the other or both. This prospect was unfazed with the same easy arm stroke delivering lightning.

“There are times when you’re out scouting and you see a kid and instantly know that he’s a stud,” said Kuntz, who left the Yanks this past spring to become Major League Soccer’s director of player relations. “I’d felt that way the year prior about [Pirates super prospect] Gregory Polanco when Stick [Michael] and I saw him in West Virginia — you just can’t wait to get back to your hotel room and write him up. But to see it from one of our kids, who hadn’t gotten any pub anywhere? Borderline transcendental. It was one of those cases where I was legitimately anxious to get back in the car and call Cash [Brian Cashman, general manager] and Billy [Eppler, assistant GM] about it.”

So he did.

“Cash, I have just seen our best pitching prospect.” Cashman asked who, Kuntz said “Luis Severino,” and for a few minutes, late March wasn’t a slog. Severino, whom the Yanks had given $225,000 in December 2011 to sign out of the Dominican, was now firmly on the organizational radar. And now he is certainly on the radar of all teams.

Severino was not on any significant top-prospect list to begin this year. But at the midseason, Baseball Prospectus had him at No. 48 and Baseball America at No. 34. Severino also was invited to the Futures Game, where he pitched a scoreless fourth. The star of the day was Rangers power phenom Joey Gallo, who dazzled with his might in batting practice and with a two-run homer in the game. But Severino delivered two mid-’90s fastballs, a changeup, then struck out Gallo looking with a slider.

Three longtime Yankees executives all said Severino is the best Yankees pitching prospect in a decade, which again might be faint praise considering the output. But they saw Joba Chamberlain, Phil Hughes and Manny Banuelos when they were considered elite.

Of course, that trio exemplifies how tough the road is from elite prospect to major league success. Nevertheless, Severino is viewed well within the game. He is the prospect asked for when, say, the Cubs are trying to move Jeff Samardzija. And multiple scouts and executives not associated with the Yanks lavished praise, with one personnel man emailing to say, “totally legit. Power stuff across the board. Easy fastball. My worry is he is not very big, but the stuff plays.”

At just 20, Severino is being fast-tracked. He made 14 starts in Low-A this season, four at High-A and was promoted to start Saturday at Double-A against the Mets’ Binghamton squad. He had a 2.45 ERA and was averaging 10 strikeouts per nine innings at the two levels, but he likely is to be restrained at Double-A, finish out what is prescribed in his innings cap.

Barring injury or trade, his next big moment will be spring training next year, which almost certainly will begin with the big club with the possibility he could join The Show in 2015. At a worrisome moment in Yankees history, it is fine if their fans dream a little about the long shot of his blossoming in conjunction with health for Masahiro Tanaka, Michael Pineda, Ivan Nova and even Banuelos and what that could mean for the near future.

Either way, Severino has come a long way from the slog of late March to the forefront of Yankees plans.