Former Cardinals outfielder Chris Duncan, who is now a popular radio personality in St. Louis on 101 ESPN, has taken a permanent leave of absence from his show "The Turn" due to an ongoing battle with brain cancer, the show announced this week.

"Dunc will be taking a permanent leave from 101 ESPN to continue his fight against cancer and focus on health," The Turn tweeted. "If you pray, please keep him in your prayers. If you don't, keep him in your thoughts. He is our brother and we miss him deeply."

The show dedicated Monday's episode to it's former co-host.

Duncan is the son of former Cardinals pitching coach Dave Duncan. The former St. Louis left fielder hit 22 home runs as a rookie during the Cardinals' 2006 World Series title run and slugged another 21 homers in 2007. He played two more seasons after that, but the end of his major league career was limited by injuries.

The 37-year-old radio host had taken a temporary leave from his show in March after he announced that he had a tumor that kept "popping up." Duncan was first diagnosed with glioblastoma in 2012. His mother died from the same disease in 2013 at 64 years old.

"Please join us in keeping former Cardinal Chris Duncan and his family in your thoughts as he continues his courageous fight against cancer," the St. Louis Cardinals tweeted.

Duncan retired with a .257 career batting average.