His apology came before a pregame ceremony in which the franchise honored its 2004 team that won Boston's first World Series championship since 1918.
"I realize that I behaved bad in Boston," Ramirez said. "The fans were great. I also played great when I was here, but I realized I behaved bad. I apologize for that. I'm a new man."
He said he has been attending church for almost a year.
During seven-plus seasons with Boston, Ramirez hit .312 with 274 home runs and 868 runs batted in before being traded to the Dodgers in 2008. While with Boston, he often jogged to first base and after fly balls, had a physical altercation with traveling secretary Jack McCormick and exhibited quirky behavior that led to the phrase "Manny being Manny."
Yu Darvish showed up to the ballpark on Wednesday with his stiff neck feeling much better, and the Texas Rangers were able to breathe a sigh of relief knowing their ace won't have to join a long list of teammates on the disabled list.