(Reuters) - Warner Bros Discovery ( WBD ) shares fell more than 4% in U.S. premarket trading on Thursday, after the media giant failed to renew broadcasting rights for the NBA games, fueling investor concerns over the future of its TNT and Max streaming service.

The National Basketball Association rejected an offer from Warner - ending their four-decade long partnership - and announced new rights agreements with Walt Disney's ( DIS ) ESPN ( DIS ), Comcast ( CMCSA )-owned NBCUniversal and Amazon.com ( AMZN ) in an 11-year deal valued at $77 billion.

"NBA rights were important in our view to the future success of the Max streaming service," said analysts at Macquarie Equity Research, adding that the loss may hasten the downturn in linear networks too.

Warner's TNT sports division, a current rights holder, said it would take "appropriate action" and could exercise its matching rights and sue NBA.

But according to some analysts, if Warner sues NBA, it could hurt the company's competitiveness in the long run as other leagues could become hesitant to strike deals with them.

Warner's stock has fallen more than 65% since it was forged by the union of WarnerMedia and Discovery in 2022. The company is set to lose more than $900 million in market value, if losses hold.

CEO David Zaslav had said in May he "was hopeful" Warner would reach an agreement with the NBA to keep the league on TNT and Max.

That, however, was in contrast with his view in 2022 when he had said "we don't have to have the NBA".

"While Turner could save $1.2B+ in rights fees, it will lose ad revenues and may face pressure to reduce affiliate fees," Rosenblatt analyst Barton Crockett said.

"The silver lining is that these pressures might make WBD more open to a breakup, which in our view could boost value."