SAN JUAN, P.R. — This used to be the climax of baseball’s peak season in Puerto Rico. The storied winter league lured many of Major League Baseball’s biggest Puerto Rican stars back to the island — from Roberto Clemente and Orlando Cepeda to Roberto Alomar and Bernie Williams — and they would regularly play before tens of thousands of fans during what was otherwise their off-season.

But that scene no longer exists. Four years after being forced to cancel an entire season, the league has only four teams. And for the first time in its history, which dates to 1938, the Puerto Rican Baseball League does not have a team based in San Juan, the capital.

The league’s struggles are merely the most vivid manifestation of a more profound, and surprising, phenomenon playing out here: the decline of baseball in a place where it was long considered the primary pastime, if not a religion. After decades of populating major league rosters with All-Stars at every position, Puerto Rico had only 20 players on Major League Baseball rosters on opening day last season. Only two made the All-Star team. (By contrast, the 1997 All-Star Game included eight Puerto Ricans.)

“We can’t even compete in the Pan American Games anymore,” said the major leaguer Alex Cora, referring to Puerto Rico’s seventh-place finish in the eight-team tournament in October.