With the Los Angeles Lakers clinging to a four-point lead with just more than five minutes left in the fourth quarter on Thursday, James -- whose eldest son, 15-year-old LeBron James Jr., is closer in age to the 23-year-old Murray than he is -- switched onto the Nuggets' supernova.
"LeBron asked for the assignment, and obviously I granted it," Lakers coach Frank Vogel said of the 35-year-old James after the Lakers' 114-108 win drew them to within one victory of the NBA Finals, as L.A. now leads the Western Conference finals 3-1.
Murray, who had 28 points on 12-for-17 shooting to that point, had helped carve a Lakers 12-point lead down to a two-possession game, eyeing the chance to steal Game 4 and even up the series.
James had other ideas. He was the only Laker to guard Murray in clutch time -- defined as the last five minutes of a game when the point differential is five or fewer -- and held him to 0-for-2 shooting.
Murray had four points in the final five minutes, but those came at the free throw line.
"I knew it was winning time, and Jamal had it going," James said of his decision to guard him.
Still trailing by four a few possessions later, the 6-foot-4, 215-pound Murray drove down the middle of the lane with the 6-foot-9, 250-pound James attached to his hip and missed a layup after double-clutching his release to try to evade James' contest with 3:46 to go.
And with 2:56 left, now down only three points, Murray drove on James again and missed, again, as the Lakers' star outstretched both of his arms to swallow up any air space as he closed on Murray from behind.
Even though James -- who finished with 26 points, 9 rebounds and 8 assists to Murray's 32 points, 3 rebounds and 8 dimes -- got the better of Murray, the Denver guard earned James' respect.
"The kid is special," James said. "He has an array of shots. Triple threat from the 3, midrange and also in the paint. For me, it's just trusting my defensive keys. Trusting my study of film. Trusting personnel. And living with the results.
"I told my teammates that I had him and everyone else can kind of stay at bay and stay home. I was able to get a couple stops, and we were able to rebound the basketball, which is the most important thing."
James, a 17-year veteran, came into the game averaging a career postseason low of 34.4 minutes in these playoffs, as Vogel has tried to manage his legs.
On Thursday, James played 38 minutes and said he was plenty prepared for his matchup with Murray down the stretch.
"I don't reserve any energy," James said. "I'm on the floor, I give it all I got. If I need a break, I ask for a break. Coach has done a good job of getting me out throughout the course of the game. I don't look at it as a reserve tank. I've got pretty good energy when I'm on the floor all the time.
"It's winning time and I don't have a chance or time to be feeling tired. I'm tired now. That's when I'm tired, when it's zeros on the clock. That's when I'm tired. I'm not tired during the game."
James defended Murray 11 times in Game 4 after matching up with him only seven times in the half-court through the first three games of the series, according to Second Spectrum data.
Murray said that James' presence was just another purple-and-gold uniform to him.
"When I see LeBron, I do the same stuff I do when I see [Alex] Caruso, and same stuff when I see [Rajon] Rondo and KCP [Kentavious Caldwell-Pope] and Kawhi [Leonard] and PG [Paul George] and Pat [Beverley] and Royce [O'Neale]," he said, rattling off the defenders he has faced this postseason. "I do the same thing. So I appreciate the respect, but we just got to win the game."
Lakers big man Anthony Davis said that having victory in sight is what motivates James to push himself in situations like the one he found himself in Game 4.
"I think he just loves challenges, honestly, especially late game," Davis said. "Just like I am with guarding the best big, he wants to guard the best perimeter player and take on the challenge. He did it the last series with James Harden. He wants to take on those challenges and make them score over him. He's a great defensive player. We trust him guarding those guys and making them finish over LeBron James. He did a hell of a job on Jamal Murray."
Indeed, James' success on Murray mirrored the defensive production he has shown all postseason. With James as their closest defender these playoffs, Murray, Harden, Russell Westbrook and Damian Lillard have shot 14-for-38 (36.8%) from the field, according to Second Spectrum. And James tightens the screws -- to borrow a favorite Vogel phrase -- even more later in the game, as opposing players have shot 7-for-28 (25%) when he contests a shot in the fourth quarter/overtime this postseason, the lowest percentage allowed by any player to defend 25 or more.
"He did a great job down the stretch trying to contain him one-on-one," Vogel said. "Murray had a great night. Nothing was really working in terms of trying to slow him down until LeBron took that assignment. Game ball to him, I guess, for that move."