Long was born in Cromwell, New Zealand. He turned professional at the age of 21 and joined the PGA Tour of Australasia in 1993. In 1996 he broke through to win the New Zealand Open. He then played on the European Tour from 1997 to 1999 and featured in the top 100 of the Official World Golf Rankings.
In 1999 Long's career was interrupted after suffering a broken neck in a body boarding accident. After making a recovery he turned his attention to America and played on the second-tier Buy.com Tour (now Nationwide Tour). He had some success at this level, winning twice, and graduated to the PGA Tour in 2002 and 2005 but was unable to keep his card on each occasion. In 2008 Long returned to Australasia and topped the 2008 Von Nida Tour money list (second tier tour).
In 2016, Michael won the 2016 Oates Victorian Open in a playoff which was his first win on the PGA Tour of Australasia in 17 years
- The only player in history to win all NZGA titles, including the NZ Open as a professional
- 1997 World Cup Team
- 1997, 1998, 1999 Dunhill Cup Team
- 2016 Oates Vic Open Champion
- 2 time winner on the Web.Com Tour