Paul Pierce has praised the Miami Heat's LeBron James after his 49 points condemned the Brooklyn Nets to defeat in New York on Monday night.

The loss handed Miami a 3-1 lead in their second-round playoff series against the Nets, and Pierce admits that there were times when he was powerless to prevent James from getting his own way in their personal duel.

"He's tough. Especially with his strength, his speed, when he ducks his head and tries to go to the basket," the 36-year-old told members of the media.

"It really took away a lot of my aggressiveness in the first quarter when I picked up two fouls, so I was trying not to pick up my third foul in the second quarter and he realized that and he just kept going to the hole, but at the end of the day, it's tough to guard him one on one."

Miami's victory means that they are one game away from the Eastern Conference finals ahead of game five on Wednesday.