Everton midfielder Pienaar celebrates his crucial strike at White Hart Lane
Steven Pienaar struck to earn Everton a narrow victory in David Moyes's 300th game in charge and end Tottenham's 100% home record under Harry Redknapp.
The South African latched on to Mikel Arteta's quick free-kick and his shot cannoned in off Vedran Corluka's shin with Heurelho Gomes stranded.
It was no more than they deserved at that point, after Gomes had denied Louis Saha and Pienaar earlier on.
Spurs responded, but Tim Howard denied Roman Pavlyuchenko to seal the win.
It was a classic away win for the Toffees, the visitors dominating proceedings for the first hour before dropping deep late in the game to repel Spurs' expected rally.
Everton moved up to seventh but victory came at a high cost with news afterwards that striker Yakubu is expected to miss the rest of the season after rupturing his Achilles.
A game of few chances - Redknapp
For their part, Tottenham will be disappointed to succumb to only their second defeat in 10 games under Redknapp but, having made a habit of winning even when not at their best under the former Pompey boss, their fortunes ran out at a chilly White Hart Lane.
For a time, though, it looked as though luck would again be on their side with Gomes producing a series of smart saves to keep them on level terms and prevent Everton converting their early dominance into goals.
The much-maligned keeper has faced a barrage of criticism of late but he showed glimpses of his returning confidence, saving from Marouane Fellaini twice from the edge of the box in a matter of seconds.
The Brazilian also did well to twice deny Saha - an early substitute for Yakubu - once when he cut out Fellaini's cross with the Frenchman poised and then when Saha found himself unmarked eight yards out only to direct his header straight at the keeper.
The Toffees were shifting the ball around with total confidence and, faced with a five-man midfield full of energy and quality, the likes of Tom Huddlestone and Bentley failed to fire early on for Tottenham.
Aaron Lennon, though, was as effervescent as he has been most of the season and he had the hosts' best chance of the half, collecting the ball in the area after a fine counter-attacking run from Didier Zokora, only to blaze his effort at goal high and wide.
If Everton fans wondered whether they might rue their team's first-half profligacy, Pienaar soon calmed their nerves.
The midfielder - in only his sixth league start of the season because of injury - latched on to Arteta's free-kick with the Spurs defence asleep and his shot was deflected past a helpless Gomes by Corluka.
Interview - Everton boss David Moyes
He almost made it two when another of his drives was deflected by Ledley King but Gomes did well to beat it away and, with Everton happy to sit and break, Spurs came back into it.
Bentley, in particular, began pulling the strings for the hosts and he carved out a great chance when his whipped cross was poked goalwards by Pavlyuchenko, but Howard did brilliantly to palm it away left-handed on the stretch.
With Everton camped in their own half with the minutes ticking down, Gareth Bale and Fraizer Campbell both forced desperate blocks from the Toffees defence late on.
But Tottenham, for once under Redknapp, could not find a breakthrough and the Londoners remain outside of the bottom three only on goal difference.
Tottenham manager Harry Redknapp: "It was a really poor goal to concede. I thought at half time the game had 0-0 written all over it and so to lose to a goal like that is very poor.
"We didn't work hard enough as runners to create space and openings for the pass so our possession wasn't good enough and if you don't pass it well you don't give yourselves a chance.
"Still, we're working at things, looking to improve, and we're by no means the finished article. Until we get the points that pull us into the top half of the table, we are very much in a dogfight and I - and the team - all know that."
Everton boss David Moyes: "I think we owed it to the fans to put in a performance after the defeat against Wigan and we certainly did that.
"Spurs' form at home is excellent of late and Harry's doing a magnificent job there so we knew it would be tough. They put us under a lot of pressure late on but we held out well.
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