PSV win, Twente and Ajax drop points in draws
Tim Matavz struck after 11 minutes to put PSV ahead but midway through the first half keeper Andreas Isaksson allowed a weak shot from Soufian El Hassnaoui to bounce over him for the equaliser.
Wijnaldum (pictured) made the difference after the break, coming in off the right flank to score two similar goals.
Twente Enschede slipped to third with 26 points after they allowed Lerin Duarte to equalise for Heracles Almelo in injury-time. Peter Wisgerhof had given Twente the lead in the 50th minute.
Ajax Amsterdam, fifth with 21 points, lost a two-goal lead in the final five minutes as they allowed visiting NAC Breda to salvage a 2-2 draw through Santi Kolk and Robbert Schilder.
Miralem Sulejmani opened the scoring for injury-hit Ajax after 35 minutes, and Derk Boerrigter doubled the lead on 84 minutes.
Ajax's second-choice striker, Dmitry Bulykin, limped off with a knee injury early in the game.