The Lakers later announced that X-rays were negative. Ball left the arena in a wheelchair and was taken to an area hospital for examination after the X-ray machine at Toyota Center malfunctioned, according to the Lakers. The second-year guard also was set to receive an MRI, according to Lakers coach Luke Walton.
Ball, who sprained the same ankle against the Denver Nuggets in late November, turned the ankle after colliding with James Ennis III with 8:39 left in the third quarter. He fell to the floor in pain and had to be carried to the locker room by Lance Stephenson and Michael Beasley during the Lakers' ensuing timeout.
"He knew it was something big," Stephenson said. "Just had to carry him back, and I know he'll be back soon."
Ball had eight points and 11 assists at the time of the injury, with seven of those assists coming in the first quarter as L.A. raced to a 39-26 lead after one. The seven assists tied his career high for assists in a quarter.
"Right when Lonzo went down, I think that's when it went away," Lakers forward Brandon Ingram said. "We lost momentum a little bit. We got away from what we were doing a little bit. I think we were still doing the same things, but some of the pressure went down a little bit and the defensive rebounding. But that's all things we can control."
Shortly after Ball's injury, with the Rockets storming back from a 21-point deficit to cut it to seven, Walton was ejected for picking up two technical fouls. Associate head coach Brian Shaw took over for Walton.
"I wasn't happy about a lot of things, but Lonzo getting hurt really took it to another level for me," Walton said after watching the rest of the game in the locker room. "The first technical I deserved. Second one, all I said was, 'You guys are funny. This is really funny.' That's all I said. I wasn't yelling anymore, I wasn't screaming anymore. I was shocked that I got thrown out for that. I've heard a lot worse, I've said a lot worse. But it is what it is."
There were several bright spots, including Stephenson filling in with 13 points and two assists in the fourth quarter and overtime combined; Ivica Zubac putting up 17 points and nine rebounds while shooting 9-for-9 from the foul line; Ingram scoring 11 points on 5-for-6 shooting in overtime; and Kyle Kuzma leading L.A. with 32 points on 12-for-19 shooting.
But there also were several blunders down the stretch.
The Lakers held a seven-point lead with 1:12 remaining in regulation and allowed the Rockets to finish the fourth on an 11-4 run, capped by a 3-pointer from Eric Gordon with two seconds remaining.
Shaw had instructed his team to foul whichever Rockets player caught the ball before the chance for a game-tying shot.
"I'm kicking myself for not stepping over and being able to get a better contest on the shot," Ingram said. "I think if I would have stepped over, I don't think he would've had anywhere to go, to shoot the basketball or to drive the basketball, so I put that one on me."
In overtime, trailing by two with 11.5 seconds left, Josh Hart turned the ball over trying to find Kuzma open in the corner.
"I turned the ball over at the end," Hart said. "We were down two with the opportunity to tie it or go ahead, and I turned the ball over. Point blank, that's where my mind is. I messed up on that one. That's where my mind is right now."
On the possession before that when trailing by one, Kentavious Caldwell-Pope air-balled a 3-pointer.
"I didn't get no lift on it, no legs," he said. "Just tried to make something happen."
Walton facetiously said at the shoot-around that his team's goal was to hold reigning MVP James Harden under 50 points. Harden finished with 48.
Now the Lakers face the prospect of being without James, Rondo and Ball when they face the Warriors, who have DeMarcus Cousins and their other All-Stars healthy.
"As a team, we just need to continue to be who we are the last two games," Kuzma said. "I think we did a great job of playmaking for one another, of making shots, hitting free throws. It's always the next man up mentality."
At the end of the night, on the white board in the visitors' locker room, there were two words written in blue ink: "Pack Mentality." It called to mind a favorite saying of Walton and Shaw's old coach, Phil Jackson, who would often recite a quote by author Rudyard Kipling: "For the strength of the pack is the wolf, and the strength of the wolf is the pack."