Appearing with his wife, Janay, Rice spoke publicly for the first time since being charged with felony assault after the February incident at a casino in Atlantic City, New Jersey.
He faces possible suspension by the National Football League.
Rice, an anti-bullying advocate and three-time Pro Bowl pick, appeared at a televised news conference to offer his apology to the Ravens coaching staff, team owner Steve Bisciotti and fans.
"Sometimes in life, you will fail," he said. "I won't call myself a failure. Failure is not getting knocked down. It's not getting back up."
He said he and his wife had spent time reflecting and working on their relationship.
"No relationship is perfect. But for me and Janay, counseling definitely did help us out," he said.
He appeared overcome with emotion several times.
"I do deeply regret the role that I played and for the incident that night," his wife added. "I love Ray, and I know he will gain your respect back in due time."
Police arrested Rice and Janay Palmer, who was then his fiancée, shortly before 3 a.m. on Feb. 15 at Atlantic City's Revel Casino and Hotel.
Surveillance recordings showed them hitting each other in the casino elevator, and Rice knocking Palmer unconscious, police said.
The couple was married the day after a New Jersey grand jury indicted Rice in March.
An assault charge against his wife has been dropped.
On Tuesday, Rice was accepted into a pre-trial intervention program, thus avoiding jail time.
Completing the program would lead to the dismissal of the assault charge, although the arrest will remain on his record.
Rice signed a five-year, $35 million contract with the Ravens in 2012 and helped Baltimore to a Super Bowl victory over the San Francisco 49ers at the end of that season.
He can still be suspended by the National Football League under its personal conduct policy.
( Source: reuters.com )