Miami Heat star LeBron James has revealed that he has been mentoring college quarterback prospect Johnny Manziel.

The 29-year-old has signed up the youngster to his marketing company, LRMR, and is hoping to be able to help as Manziel prepares for life in the NFL.

"We're happy we're able to be a friend of his and be able to help. When the opportunity was brought to me, I just told him if he's willing to listen to my advice, I was willing to give it," James told reporters.

Manziel has been involved in off-the-field incidents but remains a potential top overall pick in this year's Draft.