Rose confirmed to The Sports Business Journal on Friday that the alliance was official, and NBA Players Association spokesman Dan Wasserman confirmed to ESPN.com the union did receive the official letter, specifying that James was choosing Rose to represent him in contract negotiations, on Thursday.
Calls placed to Rose and James' attorney Fred Nance were not immediately returned.
A group of James' friends, including his high school teammate Maverick Carter and his road manager Randy Mims, are still expected to take on the marketing role. James already has more than $120 million in endorsement deals, including relationships with Nike and Coca-Cola. Over the past couple months, Carter has not divulged plans of the group's vision for the star player.
James, who is currently touring Asia on a Nike promotional tour, has two more years left under his original rookie scale contract. He will be eligible to receive a maximum six-year extension in August 2006.
Darren Rovell, who covers sports business for ESPN.com, can be reached at Darren.firstname.lastname@example.org.