Williamson was designated for assignment for the second time this year Saturday.
Williamson went unclaimed when he was DFA'd at the end of spring training, and there's a good chance the same thing happens this time around, as his poor showing in 15 games for the Giants brought the 28-year-old's career slash line down to .207/.283/.359 over parts of five seasons. Mike Yastrzemski's contract was selected in a corresponding move.