All-Star forward Carmelo Anthony made it official: He will become a free agent July 1. Anthony, who had until Monday to formally inform the Knicks of his plans, sent required paperwork to the NBA on Friday, sources close to the player disclosed.

ESPN.com reported the news on Sunday.

Anthony had until Monday to opt out of his current contract with the Knicks. That deal would have paid him $23.5 million next season.

The money, however, wasn't enough to persuade Anthony to keep his contract intact. Anthony has stated publicly on numerous occasions last season that he wants to play with a title contender.

New York finished the 2013-2014 season 37-45 and did not make the playoffs. Team president Phil Jackson met several times with Anthony in hopes of convincing him to delay free agency until next year when the Knicks will have a lot of salary-cap room.

But Anthony has preferred not to wait and will listen to pitches from the Los Angeles Lakers, Houston Rockets, Chicago Bulls and Dallas Mavericks, all of whom have expressed interest in him. There has been talk that the Miami Heat are also interested in acquiring Anthony, but team president Pat Riley has stated his priority is retaining his three stars - LeBron James, Dwyane Wade and Chris Bosh.

The Chicago Sun-Times reported that Bulls head coach Tom Thibodeau has spoken to several people who have coached Anthony in the past, seeking character evaluations.

'"I even told Tom that there may be days he will want to blow his own head off when it comes to Melo's defense, but he keeps saying he knows he can make it work," one coach told the newspaper. ''It's not that Carmelo can't play defense it's just how often. And he knows every trick in the book on getting around that.''

''There's no question [the Bulls] would be better with [Anthony], with or without his defensive inconsistencies,'' the coach said. ''As I told Tom: 'You're in the East, Tom. Remember, you're in the East.'''

Becoming a free agent doesn't guarantee Anthony will not return to the Knicks. He can make more money with the Knicks than any other team - Anthony is in line to make $129 million over five years in New York. The most he can make elsewhere is $96 million over four years.

"Carmelo loves being a Knick, he loves the city and he loves the fans," Anthony's agent Leon Rose told ESPN.com. "At this stage of his career, he just wants to explore his options."

There is the likelihood, however, that the Knicks will participate in a sign-and-trade, allowing Anthony to get a max contract with another team, while acquiring less-valuable players and/or draft picks in return. All of the teams who've expressed interest in Anthony must create cap room to sign him.

Anthony is one of the NBA's top scorers. He averaged 27.7 points per game last season; his career-scoring average is 25.3.