Relegation-threatened Huddersfield produced a stunning second-half fightback to thrash Middlesbrough and dent their automatic promotion hopes.
Marcus Forss' powerful finish put Boro ahead shortly before half-time, but Josh Ruffels lashed a shot into the roof of the net to level just 20 seconds into the second half.
The hosts led moments later when Josh Koroma curled a shot into the corner before Matty Pearson added a quickfire double as below-par Boro collapsed.
The visitors had a goal ruled out for handball before Chuba Akpom headed a consolation from Riley McGree's cross for his 26th goal of the season.