Four first-time champions have been crowned this decade — Duke, Loyola (Maryland), Denver and Yale — and top-ranked Penn State could become the fifth if it wins the N.C.A.A. tournament that begins Wednesday. The Nittany Lions have never won a tournament game before, and play in a lacrosse conference, the Big Ten, that didn’t even exist until four years ago.

“When I played, the best schools just reloaded,” said Casey Powell, a four-time Syracuse All-American and lacrosse evangelist who moved to Chicago last year to spread the game there. “Now there’s so many more players, where Johns Hopkins and Syracuse are still getting their bunch, but other schools can too. Syracuse’s exposure revolutionized the game and created a new era of lacrosse.”

Coaches, analysts and former players say parity has come primarily from the youth talent boom, as players from outside the traditional hotbeds look beyond the traditional powers. The sport was once rarely on TV and was played mostly in the East. Games are everywhere now: played by amateurs and professionals across the country and, increasingly, the world, and broadcast on TV and online, exposing the game to new audiences.

Lacrosse has been the fastest-growing U.S. team sport at the high school level for at least the past two decades, according to U.S. Lacrosse. The number of high school players doubled from 162,021 in 2006 to 324,689 in 2017. Players from California, Florida and the Midwest have created a more level playing field for schools like Denver, which became the first men’s Division I champion west of the Mississippi.