Defender Dean scored the only goal as Bournemouth beat Tottenham to climb above them in the Premier League table.
The 19-year-old was left unmarked at the back post to head home Marcus Tavernier’s inswinging corner on 17 minutes.
Huijsen’s goal extended Spurs’ poor record of dealing with set-pieces, and prompted manager Ange Postecoglou to shake his head ruefully on the touchline.
Postecoglou’s side had started well, with Dominic Solanke prominent as he returned to the Vitality Stadium following his £65m summer move.
Solanke, who was greeted by a smattering of boos, had two of the first three shots for Spurs, but they lost their way after Huijsen’s goal, and Tavernier and Evanilson had chances to extend Bournemouth’s lead in the first half.
Spurs regrouped after the break and pushed for an equaliser by bringing on captain Son Heung-min for Pape Matar Sarr, which led to chances for James Maddison, Pedro Porro and Dejan Kulusevski.
But the north Londoners gave away more chances than they created in the closing stages, and Evanilson had a goal ruled out for offside.
Spurs’ problems were compounded when Ben Davies left the field with what appeared to be a hamstring problem, leaving Postecoglou with just one fit centre-back before Sunday’s derby against Chelsea.
Spurs face familiar issues
Another setback for Tottenham will leave them open to familiar criticisms.
The fact they started the match well will be of little consolation to Postecoglou, who saw many of his players’ heads drop after Huijsen’s goal.
And it means many outsiders will focus on what is perceived to be an ongoing issue with Spurs’ mentality.
Whatever is the cause, their players looked anxious at times, most notably when Destiny Udogie hit a crossfield ball straight out of play.
Postecoglou can point to his squad being ravaged by injuries. Defenders Micky van de Ven and Cristian Romero, and goalkeeper Guglielmo Vicario would be certain starters were they fit, while Richarlison, Wilson Odobert and Mikey Moore are absent in attack.
But with just one win in six – albeit a 4-0 victory at Manchester City – and a poor set-piece record drawing scrutiny, it is clear there are problems to solve.