Roger Clemens defended his own virility on Twitter Wednesday, a day after The Daily News reported that his sexual effectiveness was a focus of a 2008 interview federal agents conducted with the pitcher's former mistress, country singer Mindy McCready. "I've taken great care of my body, and to this date and time all the pipes on this body are still working great," Clemens wrote to his nearly 3,000 followers on Twitter. McCready raises questions of Clemens romantic abilities. "It's amazing what some will say to make money off of another," Clemens wrote. "Hey here's a thought ...ever tried working for a living?"