Sessions' trey with 48 seconds remaining put the Lakers ahead to stay at 89-86, and after Denver's Andre Miller was called for offensive goaltending, Blake sealed the Lakers' win with another 3-pointer.
Sessions finished with 12 points. Blake scored eight of his 10 points in the fourth quarter for the Lakers, who will try to close out their Western Conference quarterfinal series when they host Tuesday's Game 5.
Danilo Gallinari led the Nuggets with 20 points.
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