Tremayne Cobb of C. H. Flowers demonstrates his swing. He is among a growing number of high school players paying attention to "launch angle" and "exit velocity" a trend that trickled down from MLB. (John McDonnell/The Washington Post)

The ball smacked off the bat of Tremayne Cobb Jr. and flew toward left field, sailing over the wall and into the woods behind the Bowie High baseball field.

The pitch was an inside fastball, a perfect offering for the C.H. Flowers senior shortstop to employ an approach at the plate he has spent the past year perfecting: hit the ball as hard and as high as possible. The blast to lead off the game against Bowie was perhaps the deepest of his seven home runs this season.

“I’d rather get a flyball out than a groundball out. I hate ground balls,” said Cobb, a Hartford commit whose Jaguars play Eleanor Roosevelt on Wednesday in the Maryland 4A South playoffs. “My swing, it’s just not what happens. I usually try to focus more on launch angle.”

It was only a matter of time before Major League Baseball’s fixation on exit velocity and launch angle trickled down to the high school level. It has impacted not just the way players approach the game, but also how they’re recruited by college programs and scouted by pro teams.

Exit velocity is the speed at which the ball comes off the bat — the faster, the better. Launch angle, ranging from zero to 90 degrees, is the ball’s vertical trajectory — and MLB’s statcrunchers have determined the optimal angle for extra-base hits is between 8 and 32 degrees. The terms have become part of baseball’s lexicon since MLB introduced Statcast, a camera-based analytics system that tracks the movement of players and baseballs, in 2015.

“It’s changed my game completely,” said Magruder senior first baseman Mason Crickey, who took the advice of a trainer this offseason to focus on the metrics. “My family is kind of amazed, and my teammates are loving it.”

Crickey’s results have been impressive: He was a .300 hitter as a junior and wasn’t considering baseball in college; now he’s hitting .480 with 12 doubles and hopes to walk on next season at Salisbury University.

McLean Coach John Dowling has incorporated the metrics into his practices. Last fall, the Highlanders raised money through sponsorships to purchase a Rapsodo hitting machine, a black box that retails for more than $4,000 and, when placed 14 feet from the plate, syncs each hit’s data online as the ball passes it. Since then, Dowling’s players have taken to studying MLB’s exit velocity leader board.

“Any one of them that’s turned on a baseball game in the last five years has been exposed to that,” said Dowling, in his sixth season with the Highlanders.

In March 2018, Cobb’s friend recommended Baseball Rebellion, a training facility in Durham, N.C., that has worked with professional players. Two months later, Cobb hopped into the passenger seat of his dad’s Chevrolet Suburban, and they drove five hours from Upper Marlboro, Md., for a two-hour lesson. Cobb, 17, now makes the trip almost every week.


Tremayne Cobb is batting .574 for the Jaguars. (John McDonnell/The Washington Post)

“It’s worth it,” said Cobb, who’s hitting .574. “It really started to click this past offseason. I could see how much my numbers had improved. It really hit me.”

Aaron Tarr, in his seventh season as coach at Marshall, is also a subscriber. Seeking an advantage over his counterparts in 2016, Tarr acquired an $18,000 FlightScope Baseball radar, which provides instant feedback on players’ hits and helps him form his lineups.

“If I don’t tell [his players] not to, they’ll treat BP like home run derby,” Tarr said, “and I don’t have a problem with that.”

Simpler gadgets that track the metrics cost about $300.

There’s another school of coaches who believe high school players — in a key developmental stage — should concentrate on fundamentals rather than more complex swing analysis.

“I’m not worried about exit velocity,” Riverdale Baptist Coach Aaron Graves said. “I’m worried about if a ball is hit in the gap, left-center, are my center fielder and left fielder going to communicate to get the ball.”

Hitting for power, though, has become a fundamental for some players — and the metrics have become part of the recruiting process. Over the past three years, national scouts have noticed an uptick in high school players’ training in this department, too.

“You have the opportunity to scout a player twice,” said Mike Rooney, area scout for Perfect Game USA, a national scouting service. “You can scout the player with your eyes … but now you got data to back it up. Ten years ago, you might say, ‘Hey, this kid looks like he has tremendous power.’ Now you have an actual number to put to that.”

As the number of home runs in MLB has skyrocketed over the past four years, so have the amount of strikeouts, which can be a downside to hitting for power. Marshall has encountered a strikeout issue this season, so Tarr has reduced his use of data.

Many players, including Cobb, believe the benefits outweigh the strikeouts. Entering C.H. Flowers’ game against Eleanor Roosevelt, Cobb has belted four more home runs than last season and has nearly doubled his batting average.

“It’s really exciting to watch,” C.H. Flowers Coach George Brown said. “When he comes in to do his thing, at any given moment, you can expect the ball to fly.”