Engels' equaliser appeared to have earned the relegation-threatened host a point at Villa Park, but his failure to control a long ball allowed Son to coolly steer past Pepe Reina.

Son had earlier put Spurs 2-1 in front from the rebound of a penalty awarded as a result of an Engels foul shortly before half-time, the forward's first in the game coming after team-mate Toby Alderweireld had scored at both ends.

Villa remains just a point above the bottom three, while Champions League-chasing Spurs are just one point adrift of fourth-place Chelsea.