The home fans might have expected Forest's progress to the UEFA Europa League semi-finals to inspire them. However, Forest dominated the opening 20 minutes, taking a strong lead that could have been even bigger.
Their first goal came after Guglielmo Vicario parried a shot from Morgan Gibbs-White. The resulting corner from Anthony Elanga was headed away by Pedro Porro, but only as far as Elliot Anderson, who shot from range and benefited from the ball deflecting past Vicario via Rodrigo Bentancur.
Forest's lead seemed to be growing when Anderson played a great ball over the line to Chris Wood, allowing him to poke past Vicario. Unfortunately, VAR indicated that he had strayed an inch offside, giving Spurs a temporary reprieve.
However, it was only a brief delay for Spurs, as Wood scored again, heading home from Elanga's cross and sending the visiting fans into celebration.
Spurs responded with some tangible chances, but they were ineffective. Mathys Tel sliced wide and Richarlison sent a header off target, highlighting the difference between the two teams in front of goal.
At halftime, Spurs made a change to their defense, bringing on Ben Davies and Kevin Danso for Micky van de Ven and Cristian Romero.
Despite the change, the momentum remained with Forest, and although Tel remained the most lively player for Spurs, Gibbs-White nearly sealed the win just before the hour mark, but fired wide while under pressure.
Spurs were staring at a first league double of head-to-head defeats since 1996/97, but they had a huge chance at the three-quarter mark. Dejan Kulusevski's glancing header looked to be looping in, but Harry Toffolo acrobatically cleared the ball in midair.
Forest then sat back in the remaining minutes, and Sels made two impressive saves to deny Richarlison, including a fingertip diversion from the Brazilian's downward header.
A grandstand finish seemed likely, but Richarlison finally broke through with four minutes to go, heading in a long cross from Porro. Unfortunately, it was too little, too late, and Forest were full value for their victory.
This win keeps Forest's hopes of competing with the European elite alive, exactly three decades after their famous bronze medal under Brian Clough's successor Frank Clark. Meanwhile, Spurs have now lost 17 of their last 21 league games against teams starting in the top half of the table, and are virtually assured of their first bottom-half finish since 2007/08.