In Isbister's first season with the Oilers, in 2003–04, his points total dipped to 18. After spending the locked out 2004–05 season playing for HC TWK Innsbruck of the Austrian Hockey League, Isbister was traded from Edmonton to the Boston Bruins on August 1, 2005, in exchange for a fourth round draft choice (later traded back to Boston - later traded to San Jose - San Jose selected James DeLory) in 2006.