Aardsma was a first-round pick of Brian Sabean's Giants back in '03 but was traded to the Cubs with Jerome Williams two years later for LaTroy Hawkins and cash. His peripheral stats haven't changed much since last year, and his groundball rate is actually up, but his ERA increased from 2.52 to 4.73. One plus is that he's under team control through 2012. Lopez, a potential non-tender candidate for the Mariners after the season, doesn't seem to hold much trade value despite last year's 25 home run campaign.
Sandoval has seen a big downturn this year, with a .263/.325/.384 line after last year's amazing performance garnered MVP votes. His injuries have seemingly been minor, though he is just returning from personal leave. Sandoval remains under team control through 2014 and the Giants probably aren't inclined to sell low.