[1] As a senior, he averaged 18.3 points, 10.1 rebounds and 1.5 blocks per game, being named to the All-CIF LA first team.

[1][3] He tied that feature as a sophomore, also recording his first double-double, with 10 rebounds, helping his team get past Nebraska with a narrow 64–63 win.

[6][7] Coach Craig Robinson expected Johnson to become Oregon State's focal point in offense, but was mainly used as a reserve player due to his sub-par effort on the defensive end.

[9] In his senior season Johnson achieved a career-high with 13 rebounds, also adding 15 points for his second career double-double, as Oregon State lost 83–80 to Seattle.

[10][11] A few days later, he had a career-high 6 steals, also adding 13 points, as Oregon State lost 66–60 to Texas Southern.

[1][12] Prior to the game against local rivals Oregon, Johnson commented on his opponents that they are "a feisty little bunch of dudes.".

[14] Source:[1][15] After graduating from college, Johnson was selected by the Oshawa Power to play in their 2011 pre-season squad.

[21][22] After being named in the All-NBL Canada second-team and an All-Star in the 2011–12 season, Johnson signed with the Summerside Storm in December 2012.

[15][23] He posted a season-high 34 points, along with 13 rebounds, to help the Storm overcome his former team Oshawa Power.

[41][42] On August 23, 2017, Johnson was selected by the Memphis Hustle in the NBA G League expansion draft.