PSV knew it had to defend a 17-point lead from this week onwards after NEC missed the chance to claim second place from Feyenoord with a midweek loss to FC Utrecht. Away at FC Volendam, PSV manager Peter Bosz handed Esmir Bajraktarevic another start, while also giving Ryan Flamingo his second league start since late September.
The visitors from Eindhoven got off to the hottest start with a handful of chances in the opening 20 minutes, but failed to convince after and couldn't make a dent in Volendam's defence.
A poor start to the second half gave FC Volendam the opportunity to take a chance at taking a lead, which they did in the 67th minute through Robin van Cruijsen, who scored a world-class volley to give the hosts a shock lead.
PSV kick-started their attacking engines and started creating chances again, with the biggest coming from a corner that Armando Obsipo headed just past Kayne van Oevelen's goal.
PSV eventually got back alongside FC Volendam via Dennis Man, who replaced Bajraktarevic shortly before Van Cruijsen's goal and fired the ball past Van Oevelen at his near post.
The lead didn't stand for much longer: Aurelio Oehlers was launched by Dave Kwakman and finished a one-on-one with Niek Schiks to restore Volendam's lead with three minutes to go in regular time.
Dennis Man nearly scored his second a mere minute after Oehlers put Volendam ahead, but saw his shot fly over Van Oevelen's goal with PSV's last chance of the evening.
The dominant league leaders suffered a shock defeat against FC Volendam, who became the second promoted team to beat PSV this season after Telstar did so in Eindhoven in late August.