Katie Couric, lured to the CBS News anchor position two years ago, will probably leave the job long before her contract runs out in 2011, the Wall Street Journal reports today.

The producers of 60 Minutes couldn’t have asked for a better buildup to Sunday’s scheduled broadcast of an interview with baseball’s Roger Clemens about allegations that he used illegal performance-enhancing drugs.

The stakes in that interview, already high, have been raised by the lawyer for Clemens’ chief accuser and former trainer, Brian McNamee.

He’s said that if Clemens, who has denied using the drugs, calls McNamee a liar in the interview, he’ll sue for libel.