The NY Times has an article about A-Rod’s value that includes a reference to the Giants:
…. Rodriguez’s 2007 season will be hard to repeat, but even a sizable drop-off would leave him among baseball’s elite. Nate Silver of Baseball Prospectus projected him to hit .303 with a .404 on-base percentage and a .601 slugging percentage next year, while playing a roughly average third base. (Those numbers would be slightly higher if he left Yankee Stadium, which is quite unfriendly to right-handed sluggers.)
By contrast, a mediocre veteran third baseman like San Francisco’s Pedro Feliz was hitting .249 with a .290 on-base percentage and .414 slugging percentage entering last night’s game. If the Giants were to let Feliz go and sign Rodriguez, they could probably expect to win about eight more games next season than they would if they stuck with Feliz.