Sam Breen graduated in the spring as the career leading scorer for UMass women’s basketball, but she reached a significant milestone in her senior year.

Breen became the first woman to sign with The Massachusetts Collective, an organization aiming to support UMass basketball players through name, image, and likeness (NIL) agreements, on Jan. 12. The partnership led to the creation of Turbo’s Treats — dog treats sold under the brand of Breen’s dog, with all proceeds directed to the Dakin Humane Society in Springfield.

Breen made no money from Turbo’s Treats, but earned a few hundred dollars per month from her own name, image, and likeness, often by posting on social media. The most inhibiting rule she faced: Per school policy, Breen couldn’t wear the UMass logo or imagery when she posted or appeared at an event for NIL purposes.

“I think the most surprising thing was kind of the leniency surrounding it all, because you could really do almost anything as long as you’re doing something in return for payment,’’ Breen said.

She enjoyed the process of working out agreements with The Massachusetts Collective and valued the modest income.

“I would have been appreciative of, like, $20, just because we weren’t even allowed to get a penny before,’’ she said.

Collectives — organizations that raise money from donors and use it to support NIL deals for athletes — have become a dominant force in college sports as schools enter the third academic year in which athletes have been able to profit off their likeness.

According to data from transactions on Opendorse, a leading NIL marketplace, nearly 80 percent of all NIL compensation comes from collectives, even though they account for less than 20 percent of NIL-related agreements with athletes.

Several young stars carry projected NIL valuations of more than $1 million, including basketball prince Bronny James, Louisiana State gymnast and TikTok celebrity Livvy Dunne, and LSU basketball champion Angel Reese. But their eye-popping reported agreements with brands overshadow how NIL moneymaking works for most college players like Breen.

Collectives are funding the estimated $1.17 billion that will be spent on NIL deals in the coming year. They’re loosely regulated and wildly different in size around the country, but their impact on today’s student-athletes is undeniable.

“I think collectives are definitely important and definitely a positive thing,’’ Breen said. “Whether you’re making $10 per athlete or thousands of dollars per athlete, it’s more than we would have gotten before.’’

Hesitancy around NIL isn’t stopping collectives’ rise. Opendorse counted 222 nationwide in its June report. More than half are associated with Power Five programs. Two Massachusetts schools have publicly partnered with collectives: Boston College has endorsed Friends of the Heights, and UMass has endorsed The Massachusetts Collective, the Midnight Ride Collective, and Go Mass NIL.

In March, Boston College athletic director Blake James sent out a short but noteworthy press release calling on BC fans to support student-athletes looking to profit from their NIL. The letter also addressed, and essentially endorsed, Friends of the Heights.

The message might seem odd at first — how could BC promote a group it legally can’t control? But these public endorsements are common.

“When we released our statement, it was really to inform our alumni, friends, and fan base that Friends of the Heights did exist, and that it was important for our young men and women to be able to monetize and capitalize on their name, image, and likeness opportunities,’’ James told the Globe.

Other New England universities have jumped on the collective bandwagon. Want to support a Providence athlete? Fans can go right to the school’s rosters, click on a person’s Opendorse profile, and pay for an autograph, social media shoutout, or other service through the online NIL marketplace — and Providence also has support from the Friar Family Collective. UConn has the D’Amelio Huskies Collective — founded by Marc D’Amelio, father of social media megastars Charlie and Dixie D’Amelio — as well as the Bleeding Blue Collective.

The Ivy League has no collectives but is viewed as an untapped gold mine with some of the richest alumni bases. Couldn’t supporters pool vast amounts of funds together and simply overpower other schools?

To Yale athletic director Vicky Chun, that’s just not how the alumni are thinking. They’re inclined to donate to the athletic department or contribute to the school’s endowment, and they haven’t seen a reason to change.

“I’m sure many alums are looking at the [return on investment],’’ Chun said. “And the millions that are being spent — I don’t exactly see an ROI because I still see the same teams winning. And it puts mid-majors in a precarious position because they’re trying to raise an enormous amount of money that would really benefit the programs versus going to a handful of student-athletes.’’

Northeastern has not endorsed a collective. But athletic director Jim Madigan estimates approximately 100 athletes at the university have worked out NIL deals — typically small agreements that might involve payment for running a camp, or a social media post in exchange for a gift card to a local restaurant. The school has help from an NIL marketplace and education platform called INFLCR, and Madigan has had conversations with people interested in putting a collective together.

“I understand that we need to be in this space at our level, the mid-major level, because it’s the mid-major levels getting more and more active in NIL opportunities,’’ he said. “So I understand that loud and clear. Now it’s making sure that we partner, Northeastern athletics [and] Northeastern University, with the right collective — that our goals and values are aligned.’’

Madigan can see how recruiting has changed. Even when NIL rules prohibit collectives from using money to reel in high school talent, the presence of a collective or other opportunities adds to the appeal of a program.

“Recruiting used to be an evaluation, right?’’ he said. “So we’ve moved a little bit from an evaluation model — coaches go out there and they recruit, they evaluate, and they try to attract the student — from an evaluation to an acquisition model. Who can provide the largest NIL opportunities in certain sports? The student-athletes are asking, ‘Hey, it’s great you’ve got great academics. You’ve got great facilities. What are also your NIL opportunities?’ ’’