Marion decided to join forces with LeBron James in Cleveland, passing on opportunities to sign with the Indiana Pacers, Miami Heat or the Los Angeles Clippers. The Cavaliers are expected to announce the signing of the four-time All-Star to a deal for the veteran's minimum on Monday.
Marion averaged 10.4 points and 6.5 rebounds last season for the Dallas Mavericks.
Marion made his decision after he met with his representatives in Chicago following USA Basketball's exhibition victory over Brazil late Saturday, a league source said. Cleveland general manager David Griffin was also at the game. Marion and Griffin have ties dating to their days with the Phoenix Suns.
The Cavaliers are optimistic veteran guard Ray Allen will sign with them as a free agent before training camp starts, a league source said. Allen is still trying to decide whether to continue playing or retire. Cleveland is also interested in signing a veteran center, a league source said.
ESPN.com first reported Marion's commitment to Cleveland.
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