Former NFL quarterback Ryan Leaf, a once highly touted prospect who spiraled out of the league and ended up in prison years later, said Thursday that looking at an embattled Johnny Manziel is like looking in a mirror.

Manziel has had a turbulent first two seasons in the NFL, and it came to a boiling point last weekend when his ex-girlfriend alleged in a police report that he hit her repeatedly at a Dallas hotel and while driving her home to Fort Worth on Jan. 29.

Manziel's father, Paul Manziel, told The Dallas Morning News that his son has twice declined to be admitted to area rehabilitation facilities in the last week

Leaf, 39, said in an interview with The Afternoon Show with Tim Cowlishaw and Matt Mosley on KESN-FM (103.3) he was not emotionally or behaviorally prepared for the NFL.

He was the second-overall pick in the 1998 NFL draft to the San Diego Chargers, but soon imploded and was out of the league after the 2002 season. He was with the Dallas Cowboys in 2001, playing in four games.

Leaf ran into legal troubles and became addicted to Vicodin, and he eventually was sentenced to time in prison on two separate occasions. He was released in December 2014.

"It's like a mirror. It really is," Leaf said during the radio interview. "I listen to and I hear stuff that's being said and what's going on, and it's like a mirror to me. I can relate to certain things. I called my old agent, Dave Dunn, and I got his agent's contact info and I reached out. I don't know what that meant or anything. There's a solution. There always is. But it's so hard to see when you're on this pedestal and you think you don't need help.

"You don't want to be vulnerable because you're this big, strong football player, and help means weak. And it doesn't. Asking for help might be the strongest thing you will ever do. So it's hard because it was so fun to watch him. He was a great college quarterback, and he's very capable and people want to cheer for him. And now, Cleveland dislikes him so much to the point that -- like San Diego just went on me to a point where you just got to get out of town. But me going to get out of town and getting a new start, it didn't work for me there.

"... I couldn't restart it, and I'm worried that he's not going to catch on somewhere else and be as successful as he's being as capable of being. I hope he can."

Leaf said it took prison for him to finally turn his life around.

Manziel, who is expected to be released from the Cleveland Browns in early March, spent time in a rehabilitation facility during the last NFL offseason.

He started six games for the Browns this season, his second in the league, but his time in Cleveland has been dominated by off-field incidents since he was selected in the first round of the 2014 NFL draft.

Colleen Crowley, Manziel's ex-girlfriend, said Manziel acted like he was on drugs but not intoxicated during the Jan. 29 incident, according to the police report.

"For guys that are going to go play in the NFL, college is easy. ... When you get to the NFL, you're playing against the best of the best, and if you don't have the work ethic -- like people like Peyton Manning have -- you're found out in a hurry. And that happened to me. Instead of buttoning down and trying to become better, I started fighting with the media and my teammates. It was just an imploding, chaotic version of what you don't want to happen."

Click here to listen to Leaf's full interview.