Pettitte, a former Clemens teammate, testified two weeks ago that Clemens said he had used HGH – only to say under cross-examination he might have misunderstood their conversation. Pettitte agreed with a defense lawyer there was a "50/50" chance he had misunderstood the chat from a dozen years ago.
Clemens' lawyers quickly moved to strike the testimony. They said it had "all the weight of a coin flip."
In his ruling Monday, U.S. District Judge Reggie Walton said it was up to the jury to decide how much weight to give Pettitte's testimony.