Substitute Roman Pavlyuchenko's cool second-half strike was enough to see off Sunderland and send Tottenham up to third spot in the Premier League table.
Rafael van der Vaart and Sandro wasted chances as Spurs's early dominance went unrewarded in an absorbing encounter.
The Black Cats responded and Sebastian Larsson and David Vaughan both tested home keeper Brad Friedel.
But Pavlyuchenko hit a deserved winner low into the far corner from a wonderful Van der Vaart pass.
Luka Modric then offered a late contender for miss of the year when he somehow shot over with the goal gaping.
But his glaring error did not matter as Tottenham closed out their sixth successive home victory with relative ease.
The win was all the more impressive given the home side's injury problems.
Already without attacking duo Jermain Defoe and Gareth Bale, they also lost Bale's fellow flying winger Aaron Lennon to a hamstring strain after 30 minutes.
And although they continued to threaten and look dangerous, Lennon's departure and Bale's absence meant Spurs were deprived of their most potent attacking option.
Modric and Van der Vaart provided their usual class and creativity but Harry Redknapp's team were deprived of their main cutting edge and blistering pace in wide positions.
By the time Lennon was replaced by Pavlyuchenko, Spurs should probably have been ahead.
Van der Vaart deflected Benoit Assou-Ekotto's driven shot wide when it seemed easier to turn it into the back of the net and then Sandro scuffed his shot badly after being played in by Van der Vaart, as Spurs failed to make the most of several promising positions.
The Black Cats seemed to grow in confidence following Lennon's exit and had the better of the latter stages of the first period.
Kieran Richardson tested keeper Friedel with a low, long range-strike and then, moments later, narrowly failed to get on the end of the best move of the half.
Stephane Sessegnon set Larsson free down the right and the Swede's cross was just behind Richardson as he steamed in towards goal.
Larsson then tested Brad Friedel with a firmly struck 25-yard free-kick, as the game really began to spark into life.
Wales international Vaughan, who was involved in a fascinating midfield tussle with the ever-impressive Scott Parker, then worked the American keeper again with a shot having charged forward from the halfway line.
And moments later, Jack Colback was crowded out when through on goal.
But seconds after Colback failed to get a shot away Spurs broke the deadlock when Pavlyuchenko, who had looked a little off the pace, provided a fine low finish across keeper Keiren Westwood from a sublime reverse pass from Van der Vaart.
The Russian's calm finish settled Tottenham's nerves and they should have added a second in the final 30 minutes.
Modric fluffed a staggeringly easy chance to double the lead when he shot over rather than into an unguarded net from 12 yards, after Westwood saved Emmanuel Adebayor's initial chipped effort.
Pavlyuchenko also dithered and failed to get a shot away and also shot wide, while Adebayor poked an effort straight at Westwood when well placed.
Sunderland substitute Nicklas Bendtner had the visitors' only noteworthy late chance, but blazed wildly off target after a neat one-two with Sessegnon.
The win sees the hosts move two points ahead of fourth-placed Chelsea, with the west Londoners next to visit White Hart Lane on Thursday.
Sunderland manager Martin O'Neill:
"The players put in a big effort so there is a big disappointment all round. It was a real valiant effort although when Tottenham got their goal their confidence came back and they could have put the game beyond us.
"It's a tough business and we were playing against a very good side but I never thought we were out of the game.
"You would say they had a number of chances after the goal but up until then it was touch and go.
"I thought the effort was great and when we had an opportunity to try to play, the players tried to do that.
"While it was very, very tight we always had a chance but they took their chance. It's fine margins."