Tiger Woods suffered multiple leg injuries and had to be cut from his vehicle with "jaws of life" equipment following an accident in Los Angeles.
The 15-time major winner was taken to a local hospital by ambulance after the incident early on Tuesday morning and his agent, Mark Steinberg, said the 45-year-old was taken into surgery.
Woods was the only person in the vehicle, which bore the logo of his Genesis Invitational tournament, and sustained major damage. No other vehicles were involved.
In a statement on social media, Masters chairman Fred Ridley wrote: "Tiger Woods is part of the Augusta National family, and the news of his accident is upsetting to all of us.
"We pray for him, for his full recovery and for his family during this difficult time."
A statement from Open Championship organisers the R&A read: "Our thoughts are with Tiger and his family at this time. We wish him all the very best for his recovery."
PGA Tour commissioner Jay Monahan said: "We have been made aware of Tiger Woods' car accident today. We are awaiting further information when he comes out of surgery.
"On behalf of the PGA TOUR and our players, Tiger is in our prayers and will have our full support as he recovers."