He was the hitting coach for the Toronto Blue Jays of Major League Baseball (MLB) from early 2005 to September 2007.

Brantley went on to attend Columbia-Greene Community College, starred in soccer, basketball, and baseball, and still holds several school records.

After one year at CGCC, he starred at Coastal Carolina University, and after his senior season, in 1983, was drafted by the Seattle Mariners in the second round (#30 overall).

He spent the 1990–1993 seasons with several teams in the minor leagues, finally finishing his playing career with the Yomiuri Giants in Japan.

Between 1994 and 2004, Brantley was a coach and manager in the minor leagues for the San Francisco Giants and New York Mets organizations.