Francona told the right-hander in the dugout Tuesday before Cleveland played the Kansas City Royals.
It will be the second time Masterson starts a season opener. A year ago, the 28-year-old struck out 10 over eight innings against the Blue Jays in Cleveland, allowing two hits and one run in a game that the Indians went on to lose in 16 innings, 7-4.
The Indians open in Toronto on April 2. Their home opener against the New York Yankees on April 8 already is sold out.