As a possible contingency plan if they lose Johnny Damon, the Red Sox have discussed a deal with the Mariners that would involve Matt Clement going to Seattle and center fielder Jeremy Reed coming to Boston, according to a source with direct knowledge of the discussions. The Sox, at last check, had offered Damon four years and $40 million, and during yesterday's press conference announcing Jed Hoyer and Ben Cherington as co-GMs, the team reaffirmed its commitment to bringing him back. ''We want to sign Johnny Damon," said team president and CEO Larry Lucchino, who with Hoyer will spearhead the Damon negotiations. ''We have every intention of doing so." Damon's agent, hard-line negotiator Scott Boras, said during last week's winter meetings that he had multiple offers. Asked if the Sox had reason to believe Boras is bluffing, Lucchino said, ''I'm not going to talk about that specific element of this negotiation. I think the best way to try to sign Johnny Damon, as we very much want to do, is to be silent on public commentary."