ORLANDO, Florida (Reuters) - LeBron James scored an NBA season-high 51 points on Thursday as the Miami Heat topped the Orlando Magic 104-100 and closed in on the Boston Celtics for first place in the Eastern Conference.

It marked the ninth 50-point game of James's eight seasons in the NBA and eclipsed the previous 2010-11 season high of 47 points set last month by Oklahoma City Thunder forward Kevin Durant and Los Angeles Clippers rookie Blake Griffin.

The two-times reigning NBA Most Valuable Player, who scored 23 of Miami's 30 first-quarter points, also added 11 rebounds and eight assists as the Heat moved to within 2- games of the Celtics.

(Reporting by Frank Pingue in Toronto)