After all, the Wizards had lost three consecutive games. Arenas had been held below 30 points for four straight. And James and Co. keep barely beating Washington.
So Arenas arrived at the arena four hours before tipoff, hoisting 3-pointers until he made 250, and an assortment of other shots until he made 150 of those.
Then Arenas came out of a recent personal slump by scoring 45 points -- 25 more than James -- to lead Washington past Cleveland 111-99 Saturday night, ending the Cavaliers' five-game winning streak.
"When Gil gets it going," teammate DeShawn Stevenson said, "you've got to sit back and relax and let the show go."
At one point, Arenas scored 18 of 20 Wizards points.
There was a scary moment with 2 1/2 minutes left in the game, though, when Wizards guard Jarvis Hayes went down to the floor after a collision with Cleveland's Shannon Brown. Play was stopped for about 10 minutes while Hayes was taken away on a stretcher; the Wizards later said he bruised his back and banged his head in the fall and was at a hospital for precautionary tests.
Players from both teams have acknowledged that they're building a bit of a rivalry, and if so, it's been rather one-sided. Cleveland eliminated Washington in the first round of last season's playoffs, then beat the Wizards again in a 2006-07 opener.
In that Nov. 1 game at Cleveland, Arenas was limited to seven points, part of the reason he's been averaging 18.3 on the road, where the Wizards are 0-4. He entered Saturday averaging 34.5 at home, and increased that while tying an NBA season high with seven 3-pointers.
Overall, he was 14-of-22 from the field for his 22nd career 40-point game -- and third this season, which is one more than the rest of the NBA combined.
It was quite a reversal for Arenas, whose four-game, under-30-points stretch was his longest since March 2005.
"Couldn't find a shot," Arenas said. "Couldn't feel it."
Looked that way at the start Saturday, too: He finished the first quarter with three points. But he had 15 in the second quarter, then 17 in the third, when Washington outscored Cleveland 31-16.
His total output was only two points shy of his career high on a night that he arranged for the sellout crowd of 20,173 to receive white T-shirts with his last name and number -- zero -- on the back, and his nickname, "Agent Zero" on the front.
The Cavaliers were without the injured Larry Hughes, who used to play for Washington and has given Arenas fits in the past when guarding him.
"I don't think Larry could have stopped that, either," Arenas said. "He could have tried, but I don't think he could have stopped that performance."
Said James: "The way he was in his comfort zone tonight, it didn't matter who was on him."
James shot 8-for-20 from the field and appeared to grow frustrated with some of the officiating, at one point walking away with palms up. Cavaliers coach Mike Brown drew a technical for arguing a call.
"I thought LeBron was getting hit all night, and maybe the refs thought it was something different," Mike Brown said.
Arenas did a bit of everything, including a stutter-step and a bit of a push on James, who tumbled to the floor as the Wizards' point guard hit a jumper to make it 95-76 just 1 1/2 minutes into the fourth quarter.
Washington, wearing its new gold-and-black alternate uniforms, didn't commit a single turnover while taking a 62-58 halftime lead. And the Wizards held a 41-37 edge on the boards -- the first time all season Cleveland has been outrebounded.
"More than the game plan and more than making shots -- which we hadn't done in a long time -- it was about will: What team needed it the most and what team would show that it needed it the most?" Washington coach Eddie Jordan said. "And we did."
James and several teammates watched most of No. 1 Ohio State's 42-39 college football victory over No. 2 Michigan on a large TV in the visitor's locker room. ... Hughes wore a walking boot and entered the locker room on crutches. It's not clear how long he'll be out; Hughes said he'll be checked again by doctors Tuesday.