LeBron James tumbled into the crowd and injured the wife of golfer Jason Day in the fourth quarter of the Cleveland Cavaliers' win against the Oklahoma City Thunder.
US PGA champion Day was sitting with wife Ellie in the court-side front-row seats at the Quicken Loans Arena when stumbling superstar James could not stop.
He landed apparently with all his weight on Ellie Day, who had to be carried away on a stretcher, with her neck in a brace.
James said in a post-match interview shown on ESPN: "O bviously her health is very important and hopefully she's doing well. The guys told us she's doing great now.
"G oing for a loose ball I was just trying to keep the possession going and I hate that that was the end result of it."
James stands 6ft 8in talls and weighs almost 18 stone, according to NBA statistics.
Ellie Day was taken to a local hospital for treatment, cleveland.com reported, also quoting James as saying: "She squeezed my hand, said she was fine. I think she was just a little weary."
James scored 33 points for Cleveland in their 104-100 win, which halted Oklahoma's six-game winning run.
The Charlotte Hornets, led by 35 points from Jeremy Lin, needed overtime to see off the Toronto Raptors 109-99.