Aybar joins fellow shortstops Derek Jeter and Alexei Ramirez on the AL roster. Gordon has been bothered by a sprained right wrist and received an injection Thursday.
There was no immediate announcement on a replacement for St. Louis catcher Yadier Molina, who is to have surgery Friday to repair a torn ligament in his right thumb and is likely to be sidelined for at least eight weeks.
MLB said Colorado first baseman Justin Morneau and Oakland All-Star third baseman Josh Donaldson have been picked to complete the participants for Monday's Home Run Derby at Target Field in Minneapolis. Morneau spent 11 seasons with the Twins and won the 2008 derby at old Yankee Stadium.