The Brighton defender had been sidelined since the start of October due to a muscle injury but made an immediate impact on Thursday night.
Estupinan hit a stunning, curled effort from outside the box and into the back of Guglielmo Vicario's net to send the Brighton fans jumping to their feet.
The left-back celebrated wildly with his teammates after putting his side 3-0 up, knee sliding with his arms outstretched.
Then, the 25-year-old coolly turned to the TV cameras in the stadium and shouted: "I'm back!"
Estupinan made just his 10th appearance of the season on the night, but now has two goals - the first scored against Wolves at the start of the season - and three assist to his name.
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His effort against Spurs also marked his third goal of his Brighton career.
Estupinan played a key role in the Seagulls' rise to finish in the Europa League spots last term, making 41 appearances and scoring once and providing six assists in that time.
Roberto De Zerbi's men found themselves 2-0 up at half time through Jack Hinshelwood's emphatic finish and Joao Pedro's penalty following Dejan Kulusevski's shirt pull on Danny Welbeck in the box.
Pedro then got his second and Brighton's fourth with another spot-kick moments after Estupinan's pile-driver.
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Alejo Veliz and Ben Davies each netted in the closing games of the game to make it 4-2 to set up a nervy ending for Brighton - however, it was the home side's night in the end,
Brighton are now eighth in the league, as Spurs miss out on grasping the opportunity to rise to fourth.