Grimaldi attended John F. Kennedy High School in Willingboro Township, New Jersey[1] before entering Rutgers University.
He was a four-year soccer player at Rutgers and team captain his junior and senior seasons during which time he was selected as a reserve pool player for the US Olympic Soccer team.
In 1977, Grimaldi became the 1st Rutgers soccer player drafted into the professional ranks by Coach Al Miller of the Dallas Tornado who selected him in the first round (fourth overall) of the North American Soccer League college draft.
After seeing no first team time during his rookie season with the exception of two international matches against Zenith Leningrad and Monterrey, the Tornado traded Grimaldi to the Memphis Rogues where he played sparingly over two seasons due to multiple knee injuries/surgeries In 1979, Grimaldi moved to indoor soccer with the Cleveland Force of the Major Indoor Soccer League.
In 2009, he was appointed Commissioner of the National Indoor Soccer League.