Substitute Roman Pavlyuchenko scored the winner as Tottenham overcame West Ham at White Hart Lane.
Darren Bent's close-range off-target header was the closest either side came in a fairly tepid first half.
But Pavlyuchenko replaced Bent early in the second half and had an instant impact when he turned his marker James Collins to fire into the bottom corner.
Robbie Keane went close to a second for Spurs at the death but Collins cleared his goalbound shot off the line.
For two sides with such a hotly-contested rivalry, the first half-hour of the game was remarkably tame, with Tottenham having the upper hand but failing to capitalise on their territorial advantage.
They had a penalty appeal turned down after Keane's volley bounced up and hit James Tomkins but there was no serious threat on either goal until around the half-hour mark when the West Ham defence allowed Huddlestone to advance unchallenged towards the box and try his luck with a low shot.
It was pushed away by Robert Green, who was also stretched by Keane before Bent was presented with the best chance of the game so far from a Luka Modric cross, but his header lacked both power and direction.
In the closing moments of the half David di Michele had two decent chances for West Ham, one blocked by Gomes and the other put behind for a corner by Jonathan Woodgate's knee, but these were rare threats to the home side.
Woodgate presented di Michele with probably the best chance of the game so far around the hour mark, as the defender lost his footing back-pedalling as he tried to cut out Green's route-one goalkick.
The ball fell to the Italian who only had the keeper to beat, but he did not seem to realise how much time he had and snatched at his shot.
Having failed to impose himself on the game, Bent was replaced by Pavlyuchenko, and the introduction of the Russian reaped an immediate rewards.
Vedran Corluka played the ball to Modric in the box and he found Pavlyuchenko with his back to goal - but the Russian did superbly to turn his marker and fire the ball low into the far corner of the net.
Aaron Lennon came within inches of doubling the lead with a looping long-range effort from outside the box which Green did well to push over his bar.
The England winger had another good chance towards the end, when he burst into the box, only for Green to come out and challenge him.
The ball rebounded to Keane, whose shot was heading straight for the back of the net until Collins redeemed himself for the first goal with a goal-line clearance.
Di Michele then had a great opportunity to snatch a late equaliser but dithered in the box, allowing several defenders to get back and snuff out the attack.
Tottenham manager Harry Redknapp:
"We're safe now - before today I thought we needed one more win but we can start looking up not down now.
"You know it'll never be easy in a derby, they looked to attack us on the counter so I said we had to be patient and work ball in to feet, not hit crosses - that's their strength.
"It'd be lovely if we could make Europe now for the players and the club, so that's what we'd look to do, we'll give it our best shot."