According to ESPN:
The Red Sox are having discussions with the Diamondbacks about a Julio Lugo-for-Eric Byrnes swap. Brynes would serve as a fourth outfielder for Boston; Lugo would play second base for the Diamondbacks.
This actually makes some sense. Byrnes would be the right-handed hitting 4th OF the Sox need. Over the last three seasons, Byrnes hit .283 AVG/.351 OBP/.516 SLG against lefties. Byrnes has one advantage over Baldelli: he can start if/when Drew gets hurt.