Indeed, at Yale University, where F.B.I. investigators say the longtime women’s soccer coach accepted hundreds of thousands of dollars to facilitate the admission of a recruit who did not actually play soccer, the university president, Peter Salovey, announced late last week that new oversight policies had already been put in place. The Yale athletic director will begin reviewing every proposed recruit’s credentials before admission, and recruited athletes who fail to make a team after they arrive will receive “close scrutiny,” a university statement said.

A broad overhaul of athletic admissions systems in Division I, the highest level of N.C.A.A. competition and the level the colleges in the scheme compete in, has been overdue, according to several athletic administrators interviewed in recent days.

Battles over blue-chip recruits in football and basketball already tend to be heavily scrutinized. In those upper echelon sports, if there is money changing hands, it is from coaches to recruits, not the other way around.

But in the lower-profile sports like crew, volleyball, tennis and soccer — often called the Olympic sports — there has been more room for bribes and exploitation. And the most common route in such a fraud is to designate a phony athletic prospect as a “recruited walk-on.” In nearly every case of counterfeit athletic credentials cited in last week’s indictments, from Stanford to Texas to Yale, the prospective athlete appeared to be filling the nebulous role of recruited walk-on.

Such applicants are not even assured a spot on the team. But they are often on a list of five to 20 athletes — it varies from sport to sport — that a coach is permitted to submit to the admissions department.

The two daughters of the actress Lori Loughlin, who was charged in connection with the fraud case last week, were passed off as crew recruits despite never having competed in the sport, according to federal prosecutors.