 On 17 May 2014 Grella scored his first goal for the club in a 2-0 victory over the Atlanta Silverbacks converting a penalty kick to help Carolina to a 1-0 lead.On 31 May 2014 before a regular season record crowd at WakeMed Soccer Park, Grella scored the opening goal in a 2-0 victory over the Tampa Bay Rowdies.On 17 February 2015, Grella signed with New York Red Bulls of Major League Soccer after a successful trial spell.