Prior to yesterday's series finale between the Sox and New York Yankees, baseball sources confirmed a recent New York Times report that the Sox have agreed to terms with Cuban first baseman Michel Abreu. A right-handed batter, the 26-year-old Abreu is said to have tremendous power and could figure into the Sox' future plans at first base. Following the season, of course, Sox first basemen Kevin Millar and John Olerud are among the many Red Sox players eligible for free agency. Until recently, the Sox also ranked near the bottom of major league teams in power and production from the position. The Sox gave Abreu a $425,000 signing bonus that came out of the same budget the club uses to sign its draft picks. That amount is relatively small by major league standards. One major league source said it is roughly the equivalent of what a team might pay a third-round pick.