Lazard underwent core muscle surgery this week.
He earned a game ball after making six catches for a career-high 146 yards and a touchdown in the victory over the Saints last Sunday.
Lazard has 13 catches for 254 yards and two touchdowns this season.
Kirksey’s injury originally was reported as a shoulder, but the practice report this week listed a pectoral.
Kirksey, 28, has 27 tackles this season. He has seen action on 128 defensive snaps and nine on special teams.
He played only nine games the past two seasons.