SAN FRANCISCO — Last March, Twitter and Facebook, along with other tech companies, faced off over which of them would get the rights to live-stream National Football League games on Thursday nights.

Twitter, in a rare win against larger rivals, emerged victorious with the deal. The N.F.L. saw disadvantages with some of the other bids. Facebook, for example, had set tough terms, under which the social network wanted to sell all the ads that would air during the football games, essentially cutting out the sales relationship between the N.F.L. and marketers, according to two people who asked for anonymity because the discussions were private.