De Jager was sent off in the first half for a no-arms tackle on French full-back Thomas Ramos during South Africa’s 32-17 victory on Saturday.
The committee said they had upheld the red card, and based on World Rugby’s sanctioning provisions, had initially determined that a six-match ban was appropriate. However, they reduced the sanction by two weeks.
He is set to miss Tests against Italy, Ireland and Wales, as well as a Japan League One game for his club, the Wild Knights.
De Jager will be allowed to apply to participate in World Rugby’s Coaching Intervention Programme to substitute the final match of his sanction.