– What was Michael Phelps doing before he was arrested on DUI charges early yesterday? According to TMZ and its "casino sources," he was on an eight-hour "gambling binge." The sources say Phelps was playing blackjack and drinking beer in a private VIP room at Baltimore's Horseshoe Casino starting around 5pm Monday; he left around 1am was pulled over around 1:40am a few miles from the casino. He's said to be a regular there, usually playing poker; it's not clear whether he played other card games Monday. Phelps apologized on Twitter yesterday: "I understand the severity of my actions and take full responsibility," he wrote. "I know these words may not mean much right now but I am deeply sorry to everyone I have let down."