Roberson's agent, Chris Grier Luchey, told 1050 ESPN that Roberson should sign a two-year deal for a little more than $1.6 million.
"I think they see Anthony as a guy who can come off the bench and score, providing a spark plug," Grier Luchey said.
The Knicks will now have 16 players on their roster. They will be allowed to have only 15 players when the season begins. Along with Marbury, Jerome James is also a candidate to be released. James has a year left on his contract with a player option for 2009-10, while Marbury is in the final year of his deal.
Roberson has previously played with the Warriors and the Grizzlies. He has averaged 4.1 points in 36 career NBA games. He played his college ball at Florida.
The New York Post, citing unnamed sources, first reported that the Knicks would sign Roberson.
Andrew Marchand is the managing editor of 1050 ESPN Radio in New York.