A piercing alarm sounded.
"Uh-oh," Lue said Thursday as he punched in a code to silence the screaming siren.
While Lue and his home were clearly safe, and the light-hearted moment passed quickly, it was also symbolic of Cleveland's urgent situation.
The Cavs are in a dangerous spot.
Beaten for the third time in Boston in these home-sweet-home Eastern Conference finals, Cleveland will face its second elimination game of the postseason on Friday night at Quicken Loans Arena.
Game 6 is for everything.
Except, of course, if there's a Game 7 on Sunday in Boston.
Fueled by fueled-up Boston fans who must feel some sort of birthright to see their cherished team play in the Finals , the youthful Celtics again showed zero fear or hesitation on their parquet floor on Wednesday night during a 96-83 win in Game 5 that was never in any doubt.
Despite shooting only 36 percent, the Celtics improved to 10-0 at home in the playoffs as coach Brad Stevens changed his starting lineup, shortened his rotation to seven and released waves of defenders at James, who looked worn down as he attempts to advance to the NBA Finals for the eighth consecutive year.
Lue noticed early in Game 5 that James was dragging, but he's confident the 33-year-old, who was chosen All- NBA first team for a record 12th time, will be ready to save his season and prolong what could be his final games with the Cavs.
"I know he'll be ready to play Game 6, so fatigue won't be a problem and an issue," Lue said. "I'm pretty sure a lot of guys are tired during this stretch of the year. If I had to pick one guy and choose one guy to prevail, it would be LeBron. I know he'll be great come tomorrow."
Stevens started center Aron Baynes for the first time in the series and the move helped slow James, who had been crushing the Celtics when guard Terry Rozier switched on him. Rozier fronted James and got help from Baynes, the 6-foot-10, 254-pound Australian who contributed seven rebounds, six points and attitude.
"We've got a lot of tough guys on our team," Stevens said. "But I think they all will tell you Baynes is one of the toughest we've all been around."
Now Stevens needs his team to show that same tenacity on the road, where Boston is just 1-6.
The Cavs, on the other hand, are counting on James to rebound.
He pushed as hard as he could in Game 5, but for one of the only times in what has been a transcendent 13th postseason, he couldn't summon greatness.
He didn't have his usual burst. He bent at the waist grabbing his shorts, his breathing labored. During timeouts, he wiped sweat and perhaps some frustration from his forehead.
James is tired — for good reason. His teammates are draining him.
Once again, James, who will play in his 99th game this season Friday, didn't get nearly enough help from Cleveland's other starters and Lue didn't do him any favors, either.
James had 26 points, 10 rebounds and five assists. Solid, but sub-par by his standards and he committed six turnovers and missed some makeable layups. James still managed to outscore the rest of Cleveland's starters — Kevin Love, Tristan Thompson , George Hill and J.R. Smith — 26-24.
Lue inexplicably left Kyle Korver off the floor for long stretches and following the game he curiously explained that Stevens' rotation "kind of threw us for a loop."
Asked Thursday if he wished he had done anything differently, Lue bluntly said: "No."
Thankfully, he's got James, who has six 40-point games and two buzzer-beaters in these playoffs, to save the season.
He's done it once already this spring, playing through cramps and scoring 45 points in a Game 7 win over Indiana. But he's played nine games since, and gotten less and less rest as the playoffs have progressed. His body has been forced to handle more than he imagined.
James has been down 3-2 in the conference finals before. In 2012, he faced a Game 6 elimination in Boston and scored 45 points with 15 rebounds and five rebounds as Miami won.
Now he's trying to keep this flawed Cavs team alive long enough for another trip to Boston.
On Friday, James will take the floor with his future hanging in the air. His second stint with the Cavs could end this summer if he opts out of his $35.6 million contract for next season and leaves again as a free agent, a decision he can delay again with a win.
But before he picks home or Philadelphia or Los Angeles or anywhere else, he's got at least one more game in Cleveland.
"No question in my mind that he'll bounce back," Lue said.
More AP basketball: https://apnews.com/tag/NBAbasketball
Copyright 2018 The Associated Press. All rights reserved. This material may not be published, broadcast, rewritten or redistributed.