He missed, leaving him one shy of his first 50-point playoff game, muttering to himself after.
"That's the first time I've been disappointed in myself in a win," James said.
Then he smiled, realizing his performance left nothing to complain about.
James tied his playoff career high with 49 points, Chris Bosh made the tiebreaking three-pointer with 57 seconds left, and the Heat beat the Brooklyn Nets, 102-96, on Monday night for a 3-1 Eastern Conference semifinal series lead.
James carried the Heat nearly the entire way until Bosh hit the shot that put Miami ahead for good — a play where James resisted the temptation to force a shot, instead passing to Mario Chalmers, who swung it to a wide-open Bosh.
Ray Allen followed with four free throws and James finished it off with one more, putting the Heat in position to wrap it up at home Wednesday in Game 5.
James was 16 for 24 from the field and 14 for 19 from the free-throw line in matching the 49 points he scored for Cleveland against Orlando in the 2009 Eastern Conference finals. He missed his second free throw with 1.1 seconds left.
"He was what was needed on the road and that's what makes him the best player in the game," said Heat Coach Erik Spoelstra.
Nicolas Batum had 14 points, 14 rebounds and eight assists to cut San Antonio's advantage in the series to 3-1.
Portland held Tony Parker to 14 points after he had scored 29 points or more in three of his last four playoff games. Coach Gregg Popovich sat Parker and Tim Duncan after Portland built a 20-point lead in the final quarter.
The Spurs are looking to head to the conference finals for the third straight season.