Duffy, 31, will make his third start on Opening Day, although this one is far different than the others because of the coronavirus pandemic. The game July 24 will begin a season shortened to 60 games that will last through August and September.
Right-hander Brad Keller, who started on Opening Day last season, is sidelined after testing positive for the coronavirus. He is one of four players expected to make the Royals' initial 30-man roster who are awaiting two negative tests in a 24-hour span to return to the club. The others are first baseman Ryan O'Hearn and catchers Salvador Perez and Cam Gallagher.
Duffy went 7-6 with a 4.34 ERA in 23 starts last season.