In 1986, Ervine turned professional with the Los Angeles Heat of the Western Soccer Alliance (WSA).
The Heat continued their success in 1990 and made it to the APSL title game before folding.
In 1987, Ervine joined the Wichita Wings of Major Indoor Soccer League (MISL).
In 1992 MISL folded and the Wings moved to the National Professional Soccer League (NPSL) where he played until the end of the 1993–1994 season.
Ervine ended his CISL career number eight on the goals, assists and points lists with 135, 114 and 249 respectively.
In August 1998, Ervine signed with the Sacramento Knights of the Premier Soccer Alliance.
He played again a year later as a substitute for Eric Eichmann in another tie, this time with Uruguay on February 7, 1986.