Deshawn L. Thomas, 40, was arrested Monday in Las Vegas and held without bail at the Clark County jail, police said Tuesday.
Thomas will be scheduled to appear in Las Vegas Justice Court to face felony kidnapping, robbery and conspiracy charges, police said in a statement. Jail officials said it was not immediately clear if Thomas had a lawyer.
Investigators did not immediately respond to messages seeking details of Thomas' arrest.
Walker was found unconscious on a side street near the Las Vegas Strip shortly after dawn June 16, police said. He was hospitalized for two days with facial injuries and a concussion and told investigators that about $3,000 in cash and $100,000 worth of jewelry were taken. It was not clear Tuesday if any money or jewelry had been recovered.
Police released a grainy surveillance videotape June 24, identifying the man in it as a second suspect after the arrest of 30-year-old Arfat Fadel.
Fadel remained jailed pending a preliminary hearing July 16. His lawyer has said he will plead not guilty to kidnapping, robbery and conspiracy charges. A kidnapping conviction carries a sentence of life in prison with the possibility of parole.
Investigators have said Fadel and another man appeared on surveillance videotapes at some of the same casinos and clubs where Walker partied and gambled the night of June 15. Walker was photographed spraying champagne into a crowd at the Body English nightclub at the Hard Rock hotel-casino.
Early on June 16, police say Walker willingly got into the front passenger seat of a black Range Rover in the valet parking area at the Bellagio.
Fadel and the other man "clearly and methodically lured Walker into the vehicle as he represented [an] easy target due to his level of intoxication," police said in a report. Police say Fadel was driving and the other man got in the back seat.
Walker later told police he was grabbed by the neck from behind and did not recall much more. He said he did not know who the men were.
Walker's agent, Kennard McGuire of Richmond, Texas, and a spokesman for the Raiders did not immediately respond to messages seeking comment.
Walker was a first-round draft pick in 2001 by the Green Bay Packers. He was traded to the Denver Broncos in 2006 and released last February before he was signed by Oakland to a six-year, $55 million deal.