Guillermo Barros Schelotto was not the first Argentine player to set foot on a Major League Soccer field. Statistically speaking, he was the 28th when he made his debut for the Columbus Crew in 2007.

But Schelotto’s phone still rings to this day, more than six years after he left the league, with calls from fellow Argentines looking for advice. Though Schelotto, 43, is currently the coach of Boca Juniors, the most decorated team in Argentina, most of the players who call him want to talk about other teams, about other countries, about a soccer world away from the pressure-cooker environment of Buenos Aires.

“Most of them like to talk about the cities,” Schelotto said. Many of them find a way to come.

Argentines now make up the second-largest demographic in M.L.S., trailing only Americans. According to the Elias Sports Bureau, going into this season’s openers, 98 Argentine players had been featured in an M.L.S. regular-season game since the league’s inception. Sebastian Blanco, a new designated player for Portland, made his debut in an opener Friday and became No. 99.

In a ranking by nationality, Argentines have the second-highest goal total, too. Twelve of the 22 teams in M.L.S. will start the season with at least one Argentine on their roster, a list that includes stars like Dallas’s Mauro Diaz and Montreal’s Ignacio Piatti and newcomers like Atlanta’s Hector Villalba and New York City F.C.’s Maxi Moralez.