Ajax dominated the first half but Twente opened the scoring when Marc Janko converted a 21st minute penalty after Ajax midfielder Theo Janssen fouled Luuk de Jong.
Cup winners Twente were reduced to 10 men when Steven Berghuis received his second booking early in the second half and minutes later Toby Alderweireld equalised for Ajax with a long range drive.
But Ruiz settled the match midway through the second half when he cut in from the right flank to beat goalkeeper Kenneth Vermeer with a curling shot.
LATEST ARTICLES