The disciplinary committee of the Dutch football association [KNVB] reduced the Swede's punishment on Thursday to two matches, one of which is conditionally suspended.
The 22-year-old midfielder was shown a red card when playing for Jong Feyenoord against Jong Heerenveen in the Eerste Divisie on Monday night.
Gustafson kicked out at an opponent during the reserve team match, which finished 2-2.
He was handed a four-match ban, with one match suspended, at a hearing on Wednesday but the player and Feyenoord coach Giovanni van Bronckhorst felt the punishment was too harsh.
The ex-BK Hacken player will now only miss the Eredivisie leaders' away match on Sunday against bottom club ADO Den Haag and will be back to face Sparta Rotterdam, if selected.
However, he has only appeared in two league matches for a total of 28 minutes for the first team so far this season.