Taken Eighteenth Overall in 1989, Armstrong came off the bench in his first three seasons with the Bulls, but he saw increasing minutes each year.  Armstrong was part of the Bulls first three-peat (1991-93), and he was no longer coming off of the pine in the last championship year.  Now the starting Point Guard, Armstrong led the NBA in Three-Point Field Goal Percentage (.453), and he averaged 12.3 Points per Game.  

With Jordan retiring to play baseball after the 1992-93 season, Armstrong had an increased workload on offense. The Point Guard went to the All-Star Game in 1994, and he had a career-high in PPG with 14.8.  He averaged 14.0 Points the following season, which was the same one where Jordan returned in the late winter.  Armstrong would not have another full season with MJ, as the Toronto Raptors plucked him in the Expansion Draft.