SAN FRANCISCO -- By now, it's beyond obvious that Freddy Sanchez won't be ready to rejoin the Giants on May 11, the date they earmarked last week when the second baseman began an injury rehabilitation assignment with Class A San Jose. A recent recurrence of Sanchez's right shoulder discomfort forced the Giants to withdraw him from his rehab stint for five days. Sanchez played catch on Wednesday, but manager Bruce Bochy noted that he was throwing from a 90-foot distance. That doesn't equate to the arm strength he'd need. Sanchez, who hurt himself last June 10, would need more force on his throws to be able to play the position adequately. Meanwhile, Bochy started his third second baseman in four games, installing Joaquin Arias at that spot. Arias, who made his previous three starts at shortstop, actually has played more second base as a Major Leaguer than any other position. In his 117 previous games with the Rangers, Mets and Giants, Arias has appeared at second base in 70 of them.