ESPN first reported the news.
NFL Media Insider Ian Rapoport reported on NFL Network's GameDay Morning there is no structural damage in Luck's shoulder, but it was deemed the pain was too much for the quarterback to play through.
Luck was limited in practice all week after suffering the shoulder injury in Week 3. He did not throw this week until Saturday's session, per Rapoport. Coach Chuck Pagano said Friday he had "supreme confidence" Luck would not miss playing time.
The embattled coach will turn to a 17-year veteran in Hasselbeck to lead the offense against Jacksonville. The 40-year-old backup threw 44 passes in relief of Luck last season. It will mark Hasselbeck's first career start in a Colts uniform and his first since 2012 with the Tennessee Titans. The team signed backup Josh Johnson this week as insurance behind Hasselbeck, even with Alex Tanney on the roster.