CBSSports.com wire reports

WASHINGTON -- Wearing a blue floral print dress, Eileen McNamee presented herself as a soft-spoken first-grade schoolteacher who never nagged her now-estranged husband about Roger Clemens. She went on to contradict the government's key witness many times -- and even came up with a different brand of beer to associate with the crucial evidence in the perjury trial of the former pitcher.

On a day in which the judge lost his temper twice with Clemens' lawyers, the defense turned Wednesday to the soon-to-be-ex-wife of Brian McNamee. This was the woman who McNamee testified harangued him with the words "You're going to go down! You're going to go down! You're going to go down!" -- pestering him until he saved medical waste from an alleged steroids injection of Clemens so that he wouldn't be the fall guy in any sort of drugs investigation.

She says she never said anything of the sort. She said McNamee didn't tell her back then that he was injecting Clemens, and that she wasn't especially bothered by the extended time her husband spent away from home working with the seven-time Cy Young Award winner. Brian McNamee said the days apart had become a source of friction in the marriage.

"I probably complained once in a while," Eileen McNamee said. "But I did not fuss about it."

Clemens is charged with lying when he told Congress in 2008 that he never used steroids or human growth hormone. Brian McNamee is the only witness to claim firsthand knowledge of Clemens using those substances. He testified last month that he injected Clemens in 1998, 2000 and 2001 and saved the needle and other waste from a 2001 injection. He said he put some of it in a Miller Lite can to bring home because his wife was giving him a "hard time every single day."

In testimony that sometimes sounded more like divorce court than criminal court -- the couple are undergoing contentious divorce proceedings in New York -- Eileen McNamee spun a narrative that could give the jury more pause when evaluating Brian McNamee's credibility.

Among the other differences in their stories:

Brian McNamee testified that he showed his wife the needles and other waste from the injection as soon as he got home that night, and that she played a role in putting them -- along with the beer can -- in a FedEx box. Eileen McNamee said she wasn't even aware the box was in the house until shortly afterward, when she discovered it on a shelf in the basement during a time of flooding in the neighborhood.

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