PHOENIX -- Bob Melvin was talking about the improvement of Padres reliever Steven Wilson, when the San Diego skipper dropped in some cool-kid lingo that's making the rounds in Major League Baseball these days.

"The sweeper's ended up being a really big pitch for him," Melvin said.

A few seconds later, Melvin was asked a simple question: What exactly is a sweeper?

Busted.

"I don't know," Melvin said, laughing. "It's new-age baseball talk. A slider's probably got a little more depth and the sweeper probably comes across a little more. I've made that joke, too. I still write it down as a slider."

Move over slider, curve, slurve and screwball, there's a new (ish) breaking ball that's all the rage in MLB: the sweeper. Angels superstar Shohei Ohtani uses it, as does Padres starter Yu Darvish, Yankees lefty Nestor Cortes and dozens of other pitchers.

To be truthful, it's not really a new pitch, but a new term to describe a certain type of breaking ball that's been around a long time. And it's one fans are surely noticing more this season, after MLB's Statcast created a new classification for the pitch -- meaning the "sweeper" is showing up on broadcasts and scoreboards just like "curveball" and "slider."

The 61-year-old Melvin might joke that he doesn't understand the "new-age baseball talk," but the veteran manager has a pretty good grasp of what makes a good sweeper. Its main movement is side-to-side, and it doesn't plunge downward like the normal slider or curveball.

Ohtani's sweeper is considered one of the best in today's game, with a good one producing around 20 inches of horizontal movement. But there are dozens of hurlers experimenting with the pitch, including Mets reliever Adam Ottavino.

The 37-year-old is actually one of the O.G.'s in the current sweeper world, throwing a variation of the pitch for the better part of 15 years.

Ottavino grew up in New York City idolizing breaking-ball pitchers like David Cone and Orlando Hernandez on the Yankees, and wanted to have his own big bender. The right-hander already had a conventional curveball, but because the ball would first rise out of his hand before dropping, it was easier for hitters to differentiate it from his other pitches.

"Some of the hitters I roomed with in the minors said if it didn't do that, maybe it would be more effective," Ottavino said. "So I tried to keep it low, changing the break from up to down to more right to left."

Ottavino also credited former Giants reliever Sergio Romo for his sweeper, saying it provided some inspiration.

"I tried to make it as big as I could and I think I stumbled onto something there," Ottavino said. "Now you see a lot more people doing it."

Ottavino's description of the sweeper is a good example of why it's such a coveted pitch. Sometimes, big breaking balls are easier for hitters to detect, so a tighter spin that looks more like a fastball is useful. Pitchers also have more advanced tools than ever to help them fine-tune the angle of the break on their pitches, including high-speed cameras that can measure the amount of spin and the axis of rotation for each pitch.

Wilson said the analytics he's seen indicate there's more swing-and-miss with the slider, but the sweeper produces more soft contact.

"It's a little bit risk vs. reward," Wilson said. "But I think it works for me."

Orioles starter Kyle Gibson was playing for the Phillies last season when pitching coach Caleb Cotham asked the right-hander if he wanted to mess around with his slider grip. The goal was to make the pitch move more left, instead of down.

Gibson proved to be a quick study. By his next game, he had a new pitch. The veteran said the grip wasn't that much different from his original slider -- he moved his fingers about an inch on the baseball.

"I told the catcher, warming up against the Braves, that next start, I said, 'Hey, I'm going to throw them warming up here, and I'm going to throw them when I take the mound for the first inning. If I throw a couple good ones, then we'll throw it," Gibson said.

The pitch felt good on the mound, so he included it in his arsenal. He even struck out the first batter of the game on -- you guessed it -- a sweeper.

Is it that much different from a slider? That's debatable.

But if it works, Gibson doesn't really care about its name.

"Why it's called a sweeper, I have no idea," Gibson said. "I think maybe just because people don't want to say it's a slider with more side-to-side."

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AP Baseball Writers Janie McCauley in San Francisco and Noah Trister in Baltimore contributed to this story