The 2015–16 season saw Bairstow once again appear in just 18 regular-season games, while making two starts. He played in five games on assignment with the Austin Spurs in the NBA Development League between 22 November and 7 December. On 2 March 2016, he scored a career-high eight points in 10 minutes as a starter in a 102–89 loss to the Orlando Magic.
On 17 June 2016, Bairstow was traded to the Detroit Pistons in exchange for Spencer Dinwiddie. He was waived by the Pistons on 10 July 2016.
On 18 July 2016, Bairstow signed with his hometown team, the Brisbane Bullets of the National Basketball League. Due to a shoulder injury he sustained while playing for the Boomers at the Rio Olympics, Bairstow missed the Bullets' entire preseason schedule, as well as the first two games of the regular season. In his NBL debut on 16 October, Bairstow recorded 15 points, seven rebounds and three assists off the bench in a 96–93 overtime loss to the Adelaide 36ers. On 20 December, he was ruled out for the rest of the season after scans revealed an anterior cruciate ligament injury to his left knee. He suffered the injury during overtime in Brisbane's 91–85 loss to the Illawarra Hawks the previous night. Having never previously suffered a serious injury, Bairstow had now copped two in the space of six months, including a career-threatening knee injury. In 13 games over the first two months of the 2016–17 season, he averaged 12.8 points and 6.5 rebounds per game.
In July 2016, Bairstow was named to the Boomers squad for the 2016 Summer Olympics in Rio de Janeiro, Brazil. There, he dislocated his shoulder in the pool game against Venezuela.