Is there demand for such an enterprise? Why would so many players abandon a league two decades old to come along with the Rabils?

The answer is that for most players, professional lacrosse has been a grind, even though they play a rapidly growing sport in front of affluent crowds. Even a star might barely earn $50,000 a year in salary, similar to the average pro football or basketball player in the 1930s or ’40s — when the college version of those sports overshadowed the pro one, much like lacrosse today.

Now Rabil wants to let others enjoy what he has — the chance to make a living just from the sport.

Most of the pros believe in Rabil, who is offering an average $35,000 in salary for the 14-week season, plus benefits and equity stakes, along with a national TV deal. The P.L.L., Rabil said, will have year-round paid opportunities for its players as well, such as in the P.L.L. Academy, which puts on lacrosse clinics, and at smaller exhibitions and tours.

The migration of players from the M.L.L. to the P.L.L. includes 115 former college all-Americans, 12 college player of the year winners and 10 pro most valuable players.

Money has followed Rabil, too, with the P.L.L. securing financial backing from several big investors. League officials declined to say how much has been staked, but the investments are generally based on the expectation of a return in 10 years.