The Brooklyn Nets clinched a 4-1 series win over the Boston Celtics, while reigning champions the Los Angeles Lakers are on the brink of elimination.
The Lakers, without Anthony Davis, lost 115-85 to the Phoenix Suns and trail 3-2 in the best-of-seven series.
LeBron James said the Lakers have got to be better if they want to force a game seven against the Suns.
The Lakers struggled without star forward Davis, who was ruled out with a left groin strain.
Elsewhere, the Denver Nuggets secured a 147-140 win in double-overtime against the Portland Trail Blazers.
The Blazers' Damian Lillard scored 55 points including a play-off record 12 three-pointers in defeat.
James Harden scored a 34-point triple-double in the Nets' 123-109 win, adding 10 rebounds and 10 assists.
Kyrie Irving added 25 points and Kevin Durant had 24 as the Nets shot 51.2 percent and made 15 of 32 three-point tries.
The Nets will play the Milwaukee Bucks in their first Eastern Conference semi-final since 2014.
