A "sluggish" Tiger Woods was asleep at the wheel of his black Mercedes-Benz and when awakened by police early on Monday morning, had no idea where he was, according to court documents concerning his DUI arrest in Jupiter, Florida.

Police discovered Woods buckled into his 2015 car, which was running with the brake lights and right turn signal flashing, on Military Trail south of Indian Creek Parkway. After they awakened him, he had difficulty keeping his eyes open, his speech was slurred and he was unable to stand on his own, according to documents obtained by the Palm Beach Post. Asked if he understood directions to recite the alphabet backward, he said, "Yes, recite entire national anthem backward." After the directions were explained several more times, he completed the task.

Woods, in a statement Monday night, blamed the incident on "an unexpected reaction to prescription medications." The 41-year-old underwent his fourth back surgery in April and was described by police as cooperative. A breathalyser test registered .000 and toxicology results, as well as those from a urine test, were not yet available.

An officer listed the medications Woods said he was taking as "soloxex," "vicodin," "torix" and "viox." He added that he had not taken the last of these this year. Torix and Vioxx are anti-inflammatory medications; Vicodin a painkiller.

"I didn't realise the mix of medications had affected me so strongly," Woods said in a statement Monday night. "I understand the severity of what I did and I take full responsibility for my actions."

Woods initially told police he was returning to his Florida home from a golf event in Los Angeles, but changed his story about where he was going and where he had come from, police said. He even asked police how far he was from his home on Jupiter Island and was told that he was going in the wrong direction.

Woods was charged with driving under the influence of drugs or alcohol and cited for improper stopping, standing or parking in an illegal place, according to Palm Beach County court records. He was booked at around 7am Monday and freed on his own recognisance at around 11am. He is scheduled to be arraigned on July 5.

"I would like to apologise with all my heart to my family, friends and the fans," Woods said on Monday. "I expect more from myself too. I will do everything in my power to ensure this never happens again."

Mark Steinberg, Woods's longtime agent, would not say on Monday evening whether the mix of medications Woods cited was related to his back problems. "He wanted to clarify the situation," Steinberg said Barry Svrluga by phone. "But there's nothing further to provide right now."

The Washington Post