At the start of the 2019 season, assistant manager Vinny Perth took over the club as Stephen Kenny took the position of Ireland U21 manager. Massey scored Dundalk's first goal of his tenure when he netted a header in the President's Cup against Cork City in February. During the season, he opened the scoring away to Sligo Rovers and at home to Saint Patrick's Athletic; Dundalk won both matches. Dundalk won a league and cup double for the second year running, but were beaten on penalties by Shamrock Rovers in the FAI Cup final. Massey played a total of 34 games in all competitions
