The NBA have asked LeBron James to change his protective facemask for the Miami Heat's game against the Orlando Magic later today.

The forward wore a black carbon-fibre mask over his broken nose during the team's win over the New York Knicks earlier this week, but the league have urged the reigning MVP to switch to a clear one.

"It is our understanding LeBron used the black mask because a clear one he was comfortable with wasn't ready," ESPN quotes a league spokesman as saying.

James practised with a clear mask for two days ahead of the Knicks game, but decided to use the black one as he found it easier to play with.