(CNN) As he approached a curve in the road, Tiger Woods apparently meant to hit the brakes but instead slammed on the gas -- causing a high-speed rollover crash, the Los Angeles County Sheriff's Department said Wednesday.
Six weeks after the golf legend suffered serious leg injuries, Sheriff Alex Villanueva said the main causes of the crash were speed and Woods' inability to negotiate a curve.
The SUV reached a speed of up to 87 mph, Villanueva said -- far greater than the 45 mph speed limit.
The golfer was driving a Genesis SUV around 7 a.m. February 23 when the vehicle veered off the road about 26 miles southwest of downtown Los Angeles.
Woods was driving in Rancho Palos Verdes when he hit a "Welcome to Rolling Hills Estates" sign, crossed a center divider and traveled more than 150 feet across the shoulder through shrubbery and an uprooted tree before coming to a stop, according to a search warrant affidavit of the vehicle's data recorder.
He likely mistook the gas pedal for the brakes, as no braking was detected, Capt. James Powers said.
"There is zero braking on that data recorder," but "there is 99% acceleration on the pedal," Powers said.
He said the car hit a tree, went airborne did a "pirouette" before It landed.
The SUV was traveling about 75 mph when it struck the tree, Villanueva said.
On Twitter, Woods thanked the good Samaritans who came to the crash site and called 911 and the first responders "for helping me so expertly at the scene and getting me safely to the hospital."
"I will continue to focus on my recovery and my family, and thank everyone for the overwhelming support and encouragement I've received," he wrote.
Investigators did not seek a warrant for blood tests because there was no evidence of impairment or intoxication, Powers said.
Woods said he was not under any medication and had not been drinking, the captain said.
He said the golfer appeared "dazed and confused" and said he had no recollection of the crash.
Due to his injuries, "It would not be appropriate to do field sobriety tests," Powers said.
After weeks in the hospital, Woods has been recovering at home.
"Happy to report that I am back home and continuing my recovery," Woods tweeted in March.
"I am so grateful for the support and encouragement that I have received over the past few weeks."