Johnson was selected 129th overall by the Raiders in the 2019 NFL Draft. He was a four-year letterman at Houston, appearing in 45 games at Houston from 2015-18. After joining the Cougars as a wide receiver his freshman year, Johnson converted to cornerback following his sophomore season and appeared in 23 games and made 15 starts over his final two seasons, totaling 115 tackles (88 solo), four interceptions and 16 passes defensed.