The Sox and Orioles agreed on the Lopez-for-Stern swap on Thursday evening, but the deal required the approval of commissioner Bud Selig, who must okay any deal in which one club transfers more than $1 million to the other, and for Stern to clear major-league waivers.

Selig signed off on the cash transfer yesterday, but the waivers on Stern will not expire until Monday, an industry source familiar with the situation said today.

It's unlikely Stern will clear waivers since the Tampa Bay Devil Rays have made clear they intend to block the deal by claiming Stern in retaliation for what they view to be tampering on the part of the Red Sox earlier this week.

The Devil Rays believe the Red Sox contacted Dan Lozano, the agent who represents shortstop Julio Lugo, prior to the 4 p.m. non-waiver trade deadline on Monday in an effort to determine whether Lugo would be willing to play second base in the event the Sox obtained him, and discover whether Lugo would be interested in signing a long-term contact extension with the Sox immediately. Lugo, who is eligible for free agency aftter this season, was eventually traded to the Los Angeles Dodgers.

The Red Sox acknowledge they engaged in trade tralk with the Devil Rays for Lugo, but steadfastly maintain that Lozano contacted them regarding Lugo, and not, as the Devil Rays charge, the other way around.

If, as expected, the Rays claim Stern, the Sox will be forced to withdraw him from waivers. They can't risk placing him on waivers again, since the waivers are irrevocable the second time a player goes through the process. Any team claiming Stern in that case would immediately take possession of his contract.

An industry source said the Orioles, though disappointed, would be willing to wait until the end of the season if the Devil Rays claim Stern and the Sox withdraw waivers. The two teams did not discuss sending another player in Stern's place, but have a contigency plan if Stern is injured between now and the end of the regular season.