Rather than pressing all over the pitch, a pressing trap intentionally leaves one pass open — usually out wide — and then collapses on the receiver with three or four players at once.
The full-back, the near winger and the near midfielder typically arrive together, cutting every passing lane and forcing either a throw-in, a turnover or a blind clearance.
Traps work best against possession-based teams that trust their build-up. Against long-ball sides they rarely trigger, so teams need a mid-block as a fallback.