Daley Blind's late winner saw Ajax beat 10-man PEC Zwolle 2-1 and close the gap on Eredivisie leaders PSV Eindhoven.
Dusan Tadic put Ajax ahead with a 32nd-minute header after lowly Zwolle had lost goalkeeper Mickey van der Hart to a finger injury.
Zwolle equalised after 79 minutes when Vito Van Crooij scored their first goal in over six and a half hours of football.
Blind restored Ajax's lead four minutes from time when he headed home substitute Noa Lang's cross.
Van Crooij was sent off in the dying seconds after picking up a second yellow card and Ajax held on to move within two points of PSV.