Jake Livermore had opened the scoring against his old club in the first 10 minutes in a poor first half for Spurs but Harry Kane tapped in an equaliser before the Dane's strike
Jake Livermore put a 25-yard screamer past his former side within the first 10 minutes at the KC Stadium and Spurs would have been even further behind at half-time were it not for vital saves from Hugo Lloris.
But increased pressure in the second half - thanks in part to the Tigers being put a man down when Gaston Ramirez was ejected for a petulant outburst towards Jan Vertonghen - resulted in Harry Kane tapping in an equaliser on the hour.
And just as it seemed that the match was drifting away from Mauricio Pochettino's side, Eriksen popped up with a low finish past Allan McGregor to steal the points.
Tottenham had been beaten by Stoke City before the international break and their manager got the response for which he was looking, while Hull only have two victories to their name in the top flight this term.
Fit-again defender Michael Dawson returned to face his former club as one of six changes to the Hull side who lost at Burnley, with McGregor, Ramirez, Andrew Robertson, Hatem Ben Arfa and Nikica Jelavic also starting.
Pochettino also made six changes, as Eric Dier, Vertonghen, Ben Davies, Mousa Dembele, Erik Lamela and Roberto Soldado came into the side. Captain Younes Kaboul and striker Emmanuel Adebayor were not involved.
Hull had failed to score in their last three games but were in front after only eight minutes when Livermore returned to haunt Tottenham. The midfielder conceded in the build-up that it would be strange to face his former club and he looked unsure how to react after letting fly with a right-footed strike that found the far corner of the net from 20 yards out.
Davies then spared stand-in captain Lloris's blushes when he blocked Ramirez's effort after the France goalkeeper had flapped at a free kick 19 minutes in.
The Tottenham star showed his class with a fine reflex save down to his left to deny Robbie Brady before Ben Arfa blazed a shot over the crossbar after Lloris had palmed Ramirez's left-footed strike into his path.
McGregor was called into action at the other end eight minutes before half-time, palming away Lamela's well-struck shot following a swift break, and Hull breathed a sigh of relief when Eriksen flashed a dangerous ball across the face of the goal but nobody was on the end of it.
Pochettino replaced Dier, who had been booked in the first half, with Vlad Chiriches at the break and Tottenham's chances of getting back into the game were enhanced when Ramirez was dismissed five minutes into the second half.
Referee Craig Pawson gave the Uruguayan his marching orders after his assistant spotted an off-the-ball incident between him and Vertonghen.
Hull boss Bruce was furious with the decision and he was left even more frustrated when Tottenham equalised after 61 minutes. Kane was on hand to turn the ball into an empty net after Eriksen's sublime free kick had struck the woodwork.
Kane ought to have put the visitors in front when substitute Aaron Lennon picked him out with a precise cross but the striker somehow headed wide from close range and Lamela blazed a shot over the crossbar after cutting in from the left as Tottenham dominated.
But Eriksen won it in the final minute as he made space for himself and unleashed a right-footed strike which found the far corner of the net.