The 34-year-old's status with the team has been in question since undergoing ankle surgery in October.
The news of Marshall's release comes just a day after he told Bryant in a since-deleted Instagram post that there was "no room" for Bryant on the Giants, who still have Odell Beckham, Jr., Sterling Shepard and Evan Engram on the depth chart.
Yes, one big wide receiver leaving could mean the door is open for another big receiver to enter.
Speculation has already begun to mount that the Giants may turn to Dez Bryant as a potential replacement for Marshall, which general manager Dave Gettleman would not deny during his pre-draft press conference on Thursday. "We'll do our film work and you never know". To make that prediction come true, he would have to sign with one of the other three teams in the NFC East.
The Giants may also look to add a receiver to their roster in the upcoming draft.
Marshall needs 41 receptions to reach 1,000 for his career, and needs 23 to tie Randy Moss for 15th-most catches in National Football League history.