Cotton reported to the Giants' major-league facility and is active ahead of Wednesday's game against Colorado.
After being designated for assignment by the Twins for the fourth time this season Thursday and then claimed by San Francisco on Sunday, Cotton is officially ready to make his Giants debut. The 30-year-old reliever holds a 2.83 ERA and 1.11 WHIP over 35 innings of work this season. Sean Hjelle was optioned to Triple-A Sacramento in order to make room for Cotton on the roster.