CLEVELAND — With Johnny Manziel’s professional career in doubt and his personal life crumbling, his father fears for the troubled quarterback’s safety.

Manziel is facing a criminal investigation by police following allegations that he hit his former girlfriend last weekend in Texas. He was dropped by his agent Friday, was ordered this week to stay away from his ex for two years and will be released by the Cleveland Browns next month after two tumultuous seasons.

“I truly believe if they can’t get him help, he won’t live to see his 24th birthday,” Paul Manziel told The Dallas Morning News.

Manziel’s father said the family has made two unsuccessful attempts in the past week to get the player into a rehab clinic.

Manziel agreed to go to the Enterhealth Ranch addiction facility in Van Alstyne, Texas, but he would not stay, Paul Manziel told the Morning News. He tried to have his son admitted Tuesday to Carrollton Springs Hospital, but Manziel was allowed to leave. Paul Manziel said he told a Denton County Sheriff officer he believed his son to be suicidal.

Paul Manziel did not immediately return a phone message left by The Associated Press.

The 2012 Heisman Trophy winner, who entered the NFL with a party-boy reputation, spent 73 days last winter in a Pennsylvania treatment center specializing in care for alcohol and drug dependency.

The disturbing portrait of Manziel comes as his agent dropped the 23-year-old quarterback as a client. Erik Burkhardt said that with “deep regret” he has ended the business relationship. He added that he made his decision after “several emotional and very personal discussions with his family, his doctors, and my client himself.”

“Though I will remain a friend and Johnny supporter, and he knows I have worked tirelessly to arrange a number of professional options for him to continue to pursue, it has become painfully obvious that his future rests solely in his own hands,” the agent said in a statement.

“His family and I have gone to great lengths to outline the steps we feel he must take to get his life in order. Accountability is the foundation of any relationship, and without it the function of my work is counterproductive. I truly wish the best for Johnny and sincerely hope he can, and will, find the kind of peace and happiness he deserves.”

Manziel is under police investigation for allegedly hitting ex-girlfriend Colleen Crowley. She told police the former Texas A&M star struck her “several times” at a Dallas hotel and later when they drove back to her apartment in Fort Worth. The police departments in both cities said Thursday that their investigations were closed, but Dallas police said Friday that it was reopening its investigation after receiving a complaint of a domestic violence assault.

Police said detectives would determine what, if any, criminal charges Manziel would face. They noted it is not uncommon for victims of domestic violence to question or delay reporting an assault.

Crowley filed a protective order against Manziel this week that prevents him from seeing her for two years, according to the order first obtained by television station WFAA.