Dimitar Berbatov's late strike gave Tottenham their first Premier League away win of the season at Portsmouth.
Berbatov finished off a flowing Tottenham move
The game had looked to be heading for a draw before the Bulgarian ghosted in at the back post to tap home Aaron Lennon's delightful clipped cross.
David Nugent had earlier squandered a chance to put a wasteful Pompey side in front when he headed Niko Kranjcar's corner narrowly over the bar.
Spurs finished stronger with Jermain Defoe hitting the post late on.
Pompey had failed to find the net in four of their last five league matches at Fratton Park.
But with the visitors yielding 29 goals already in the league this season and without an away league win, the hosts missed the opportunity to end their barren run and move into the top four.
Spurs held firm after a first 45 minutes that was evenly contested and deserved their win for their ambition shown in the second period.
Portsmouth failed to seriously trouble Paul Robinson thanks to the excellent defenders in front of him.
Tottenham showed plenty of endeavour going forward too, with Berbatov showing touches of brilliance up front and he was denied the opener by a last-ditch tackle by Sol Campbell.
The visitors were often guilty of over-elaborating on the edge of David James' box with Darren Bent twice failing to test the keeper with a low left-foot drive from close in and a curling effort from 20 yards.
Boateng came close to scoring his first goal for Spurs but could only pick out James in the centre of the goal when he had time to place it either side, while Malbranque turned home James' parry only to see the flag raised for offside.
Portsmouth hit back with Robinson doing well to hold Sulley Muntari's powerful low free-kick, while the Ghanaian played in Diop, who had his hooked shot deflected narrowly wide by Didier Zokora.
Jenas did well to handle Kranjcar's craft in midfield
Spurs looked the most potent after the break as Lennon began to cause havoc down the right flank.
The winger whipped in a dangerous cross that was superbly tipped out of reach of the on-rushing Bent with Campbell clearing the loose ball.
The game became stretched as both teams opened up and went for the win, but clear chances were at a premium, particularly for the home side.
Substitute Nugent wasted the best of Pompey's opportunities when he climbed well only to head Kranjcar's corner over.
But when Lennon clipped his pin-point cross to the back post finding Berbatov, the striker steered home on 81 minutes to put the game beyond the home side.
Defoe almost doubled the lead in the closing stages when he raced beyond Campbell and fired his shot against the post.
And the visitors closed out the game to continue Spurs' resurgence under Juande Ramos.
Portsmouth manager Harry Redknapp:
"We got well beat, Spurs were the better team, we never got started and full credit to Spurs. I would have been happy with 0-0 but they nicked it.
"We had a bad day today, our first for 11 games. We didn't play well and they did, that's all there is to it.
"It's our first defeat at home for a while so it's not a major problem."
Tottenham assistant manager Gus Poyet:
"The performance was excellent, every aspect of the game was perfect. Didier Zokora was outstanding and the whole team defended very well.
"Everyone knows the quality going forward but the key for us is to keep a clean sheet.
"Now we showed everyone that we can do that. We came here to win that was the attitude from everyone."
Portsmouth: James, Johnson, Campbell, Distin, Pamarot (Hreidarsson 74), Utaka, Diop, Pedro Mendes (Davis 46), Muntari (Nugent 65), Kranjcar, Mwaruwari.
Subs Not Used: Ashdown, Taylor.
Booked: Pedro Mendes, Kranjcar, Distin.
Tottenham: Robinson, Chimbonda, Zokora, Kaboul, Lee, Lennon (Tainio 86), Jenas, Boateng (O'Hara 78), Malbranque, Berbatov, Bent (Defoe 74).
Subs Not Used: Cerny, Stalteri.
Booked: Malbranque, Berbatov.
Goal: Berbatov 81.
Ref: Martin Atkinson (W Yorkshire).