Baltimore - American swimmer Michael Phelps, the most decorated Olympian of all time, pleaded guilty on Friday to driving under the influence of alcohol and received 18 months of supervised probation and a one-year suspended jail sentence.
The 18-time Olympic gold medalist was arrested for drunken driving early on Sept. 30 after speeding and then crossing the double yellow lines inside a Baltimore tunnel, police said.
"The last three months of my life have been some of the hardest times I've ever gone through, some of the biggest learning experiences I've ever had," Phelps, wearing a dark suit, white shirt and blue tie, told reporters.
"I'm happy to be moving forward. I'll continue to grow from this."
Phelps, 29, was clocked by radar at around 01:40 traveling 135km/h in a 72km/h zone, police said, adding that he blew a .14 on a Breathalyzer, nearly twice the legal limit of .08 in Maryland.
He faced up to a year in jail and a $1 000 fine.
"I hope we don't have this conversation again and I'm optimistic that we won't have this conversation again," Judge Nathan Braverman told Phelps during his sentencing.
Among the observers in the courtroom were Phelps' mother, Debbie, his two sisters, and close friend Ray Lewis, the retired 13-time Pro Bowl linebacker for the Baltimore Ravens.
Police said an officer followed Phelps' 2014 Land Rover onto northbound Interstate 95, through the Fort McHenry Tunnel, and pulled him over just beyond the tunnel's toll plaza.
The drunken-driving arrest was the second for Phelps, who has spent most his life working feverishly in the pool but admits he likes to have a good time when not competing.
Following his arrest, Phelps, who is eyeing a spot on the US team for the 2016 Olympics, was suspended for six months by USA Swimming and barred from representing the United States at the 2015 FINA World Swimming Championships in Russia.
Phelps said he completed a 45-day rehab programme at an Arizona treatment center following his arrest, continues aftercare in Baltimore, and will participate in Alcoholics Anonymous.
"What I did was wrong, and I made a bad mistake," Phelps told Braverman. "I'm looking forward to having a much brighter future than I had in the past."
Phelps was charged in Salisbury, Maryland, in 2004 for drunken driving. He pleaded guilty to a lesser charge of driving while impaired in exchange for 18 months' probation.