Montreal Expos

In his first professional season, 1989, with the Gulf Coast League Expos he went 2–1 with a 2.66 ERA in seven games, three starts.

While with the Short-Season Jamestown Expos in 1990 Aucoin compiled a record of 1–3 with a 4.46 ERA in eight games, all starts.

His next two seasons, 1991 and 1992, were spent at the Class-A level. In 1991, he went 3–6 with a 4.28 ERA in 41 games, four starts with the Sumter Flyers. In 1992, he went 3–2 with a 3.00 ERA in 39 games, two starts with the Rockford Expos.

Aucoin was promoted to the Advanced-A West Palm Beach Expos in 1993. He compiled a record of 4–4 with a 4.24 ERA in 38 games, six starts.

In 1994 Aucoin split the season between West Palm Beach and the Double-A Harrisburg Senators of the Eastern League He went a combined 3–4 with a 2.82 ERA in 38 games. Staying at Harrisburg in 1995 he went 2–4 with a 4.96 ERA in 29 games.

Aucoin split the 1996 season between the Expos and the Triple-A Ottawa Lynx of the International League. With Ottawa, he went 3–5 with a 3.96 ERA in 52 games. On 21 May 1996 he made his Major League debut against the San Francisco Giants. In 2⁄3 of an inning, he gave up one earned run and registered a loss. He would finish his Major League Career going 0–1 with a 3.38 ERA in two games.

With West Palm Beach and Ottawa in 1997 he went a combined 0–1 with a very poor 11.37 ERA through 25 games.

New York Mets

In his final season, 1998, Aucoin split the season between the Gulf Coast League Mets, the Advanced-A St. Lucie Mets, the Double-A Binghamton Mets and the Triple-A Norfolk Tides. He went a combined 1–0 with a 6.21 ERA in 28 games.