Beckham said Cassidy tried to run away when he yelled at him before the former professional athlete chased him down.
According to a probable cause affidavit cited by the Miami Herald, Beckham's daughter had just gotten out of the shower and was getting dressed in her bedroom when her dad spotted a man crouching outside her windows.
The man's trousers were partially down and he was masturbating, said Beckham. "I'm sorry that it happened to him", Beckham said.
"I waited for a second, and I looked again", Beckham told the station, "and I see a white male, and he's standing by my window, and he's trying to get a better position".
Beckham played at UW-Stout from 1997-2002 before being drafted in the 4th round in 2002 by the Tennessee Titans.
Police then arrested Geoffrey Cassidy.
More news: Shocking video captures child falling out of moving carHowever, the man refused to say where his vehicle was and told police he was a 'transient.
Police reportedly arrested Cassidy for lewd and lascivious behavior with a victim younger than 16 years old.
Cassidy was treated for fractures in his face at a local hospital.
Palm Beach County Sheriff's Office/Getty Images Geoffrey Cassidy, left, received a beating after ex-NFL defensive back Tony Beckham, right, allegedly caught him masturbating outside his house.
That's when Beckham said he made a decision to have a "good conversation" with the man, 48-year-old Geoffrey Cassidy. The family have since installed blackout blinds to shield their home from prying eyes. He spent four seasons with the Titans and one with the Detroit Lions.
