A week after the Marlins shocked everyone by announcing his callup, 20-year-old Jose Fernandez allowed one run in five innings and struck out eight Mets in his major league debut Sunday.

Fernandez, regarded as one of the game’s top five pitching prospects, was expected to spend the bulk of the season in the minors. In fact, he made just one two-inning appearance for the Marlins this spring before being sent down. The team, though, had a change of heart when both Henderson Alvarez and Nathan Eovaldi came down with sore shoulder at the end of the spring.