Texas Rangers' relief pitcher Matt Bush has been trying to live a clean life since he was released from prison in October last year after serving 51 months in jail for a DUI sentence in 2012.

Bush, formerly an alcoholic and a convicted felon, says he is sober now and is seeking the help of God to overcome his problems.

"I knew I really needed help. It takes a big man to be able to admit that you have a problem, and need to get well," Bush told USA Today on Tuesday. "It's no fun living in that sorrow, that spiralling downfall. In the past, I wanted to do everything on my own, and it always failed that way. This time, I leaned on God for the help and support, allowing the (Rangers) organisation to help me, give me guidance and structure."

The Texas Rangers signed up Bush last December despite the criticisms hurled against him.

"I hear nasty things, people talking about prison and my drinking, just stupid stuff,'' said Bush.

What he does is not to be "too judgmental" and focus on his play. He said when things get bad, he thinks of Jackie Robinson, the first black American to play in the major league in the 20th century.

"Gosh, look at what he had to endure and go through, and he didn't do anything wrong. It was just because of the colour of his skin,'' Bush said.

Bush was sentenced in December 2012 to 52 months in prison for three felony counts for crashing into 72-year-old Anthony Tufano while drunk, driving over his head and leaving the crime scene.

He has been sober for a little over four years before making his major league debut last May.

"He has been unbelievable,'' said Rangers pitching coach Doug Brocail. "A lot of his success is self-taught. He had quite a bit of time to sit back and do the things he needed to do to get back in this game.

Bush believes he became alcoholic at around 20 or 21. Because of his previous convictions, he has been banned from driving and drinking for 10 years.

"I've always had the talent, and have always loved this game, but I had demons that have held me back. They kept me down. Now, I've got another chance. And I'm making the most of it. I'm not the same person I was. I don't ever want to be that person again. I'm sober. I like myself now. Really, it's the happiest I've ever been in my life," he said.