Yahoo and the National Football League are touting the first free, global live Internet broadcast of an NFL game as a success — but estimates of the audience figures were well below the league’s TV broadcasts. And how much of the game viewers actually watched and whether Yahoo lost money on the stunt remains murky.

The companies claimed 15.2 million unique viewers logged in to Sunday’s matchup from London between the Buffalo Bills and the Jacksonville Jaguars. About 66% of those, or about 10 million people, were in the U.S.

The game hit over 33.6 million total views across all devices on Yahoo and Tumblr, amounting to more than 460 million total minutes of the game. In part, Yahoo achieved those audience numbers by auto-streaming video on yahoo.com and in several of its apps, so it’s likely millions of users who didn’t even intend to watch the game caught a few minutes.

“With it being auto-played on the homepage, (average viewing time) numbers would be skewed,” said streaming-industry consultant Dan Rayburn.

The data from Yahoo and the NFL implies the viewership of the Bill-Jaguars contest averaged 2.36 million per minute, according to CNN’s analysis — far less than NFL games on TV. (ESPN’s “Monday Night Football,” for example, is averaging 13.5 million viewers.) The actual game (which Jacksonville won, 34-31) lasted 3 hours and 15 minutes, kicking off at 9:35 a.m. ET and ending at 12:50 p.m.

However, according to Rayburn, it’s impossible to determine average concurrent viewership based on the data publicly released by Yahoo and the NFL. That’s because users may have been streaming it on multiple devices.

Yahoo had signed up about 30 advertisers, and guaranteed them an audience of at least 3.5 million. The Internet company paid an estimated $15 million to the NFL for the rights; that doesn’t include Yahoo’s costs for marketing, streaming bandwidth and what it paid CBS to produce it. Yahoo said it sold out ad inventory, but that was after it chopped rates from $200,000 per 30-second spot to $50,000, according to reports.

Whether Yahoo actually made money on the NFL live-stream, the company was banking on a promotional lift from the event. It was trying to push users to its fantasy football site, and used the NFL game to showcase its live-video portfolio to marketers.

The NFL sees the Yahoo experiment as a win, because the league was able to take a game that would have had relatively low TV-viewing numbers in the States — because of the 9:30 a.m. ET start time, for starters — and attracted a larger audience by distributing it digitally to users in 185 countries.

“We’re thrilled with the results of our initial step distributing an NFL game to a worldwide audience and with the work of our partner, Yahoo,” said Hans Schroeder, NFL’s senior VP of media strategy, business development and sales.

The companies claimed users experienced minimal technical difficulties, and there were no reports of widespread issues with the Bills-Jaguar live stream, as has beset some past large-scale Internet video broadcasts.

Yahoo said viewers experienced average rebuffering ratio of less than 1%. The streams reached up to HD quality with maximum bit rates over 6.74 megabits per second and 60 frames per second, according to the companies. However, if there was congestion or not enough bandwidth, the video quality dropped significantly.

According to the NFL, the audience for the Oct. 25 Bills-Jaguars game will likely include another 1 million viewers in addition to the 15.2 million through Yahoo. That would factor in TV audience from two CBS affiliates that aired the game in Buffalo (WIVB) and Jacksonville, Fla. (WJAX); the television audience in the U.K. via Sky and BBC pacts; and digital viewing in China.