Los Angeles (AFP) - NBA superstar LeBron James collided with the wife of Australian golfer Jason Day in a scary sideline incident at a Cleveland Cavaliers home game on Thursday.

Ellie Day, sitting courtside with her husband, was stretchered off and taken to hospital after James, chasing a loose ball, crashed into her seat, with both of them sprawling backwards to the floor.

The game was halted for several minutes as medical personnel attended to Ellie, with James and his Cavaliers team-mates looking on.

"It wasn't anything out of the usual besides the injury," James said of the incident.

"But to me, obviously her health is very important and hopefully she's doing well.

"The guys told me she's doing great."

James added: "I was going for a loose ball. Just trying to keep a possession going and I hate that was the end result of it."

Ellie was reported to be alert and talking as her husband accompanied her to an ambulance, but was hospitalised overnight for observation. She gave birth to the couple's second child, a daughter, in November.

The Days, who have a home in Columbus, Ohio, were sitting courtside when the incident occurred late in the fourth quarter of the Cavaliers' 104-100 victory over Oklahoma City Thunder.

Cavaliers coach David Blatt said he had long been concerned about the danger of players colliding with courtside spectators. But James said being close to the action was a "great experience" for fans.