West Ham United 0-1 Tottenham Hotspur

Defender Eric Dier joined Tottenham from Sporting Lisbon in the summer

• Pochettino wins first league game as Spurs boss

• Defender Dier scores winner in stoppage time on debut

• Noble missed a first-half penalty for West Ham

• Naughton sent off for Tottenham in first half

• Collins dismissed for Hammers in second half

Defender Eric Dier scored a dramatic winner on his Tottenham debut to give Mauricio Pochettino the perfect start to his career as Spurs boss with victory at West Ham.

Both sides finished the game with 10 men, with Tottenham's Kyle Naughton sent off for handling inside the area.

Mark Noble fired wide from the spot-kick before the Hammers had James Collins sent off for a second booking.

But Dier, who joined Spurs this summer, raced through late on to fire home.

Midway through the second half, a fan ran onto the pitch and took a free-kick

It was a little harsh on West Ham, who had been the better side for much of the game and will be left to rue Noble's surprise failure from the spot.

The midfielder had converted all 10 of his previous penalties, but scuffed this one wide in the first half.

The defeat will also put further pressure on Hammers boss Sam Allardyce, who has an already uneasy relationship with supporters after a dismal end to last season in which they lost eight of their final 11 games.

For Spurs fans, though, the win will give them optimism as they head into another new era, with Pochettino the club's 10th manager in 12 years following his arrival from Southampton in the summer.

He was appointed with a top-four finish the target, as well as the hope that he would be able to instil in Tottenham's players the ability to play the attractive, passing style he cultivated at Southampton.

Pochettino has to achieve that with a largely unchanged squad from last season, but he was able to hand a debut to 20-year-old defender Dier, who joined Spurs from Portuguese side Sporting Lisbon.

Dier, playing initially at centre-half, was kept busy for much of the first half as the Hammers had the better of the early stages.

Carlton Cole, leading the line in the absence of injured striker Andy Carroll, curled an effort over the bar in the fifth minute, before impressive debutant Cheikhou Kouyate, signed in the summer from Anderlecht, nodded just wide.

It seemed as though the home side would get the reward their bright start deserved when they were awarded a penalty midway through the first half, as Naughton threw his hands up to deny Kevin Nolan's shot just in front of the goalline and the assistant referee flagged for the spot kick.

Naughton was subsequently sent off, but his side were saved when Noble uncharacteristically swept wide of the upright, much to the relief of Spurs boss Pochettino.

He reacted to Naughton's dismissal by switching to a 4-4-1 formation, but it did little to quell the West Ham attacks as Ricardo Vaz Te headed straight at Hugo Lloris shortly before the break, before the impressive Stewart Downing saw a fierce low drive beaten away by Lloris early in the second half.

Mark Noble had scored his last 10 Premier League penalties before his miss against Tottenham

But the balance of play swung in Tottenham's favour when West Ham's one-man advantage was wiped out as Collins received his second booking for halting the run of Emmanuel Adebayor.

Christian Eriksen curled the subsequent free-kick over the bar but the away side pressed as Andros Townsend saw two stinging efforts from distance denied by West Ham keeper Adrian.

The Hammers' lack of cutting edge in attack, which had been weakened by the absence of Carroll, was evident as they created 18 chances, but found the target on just four occasions.

New signing Enner Valencia, who scored three goals for Ecuador at the World Cup, was introduced late on in a bid to rectify their struggles in the final third, but the forward was evidently short of match fitness.

Instead, it was the impressive Downing who almost sealed victory as he broke through the defence but shot straight at Lloris.

It was a missed opportunity that they were soon to rue as England under-21 international Dier, who had drifted into attack as the game went into stoppage time, snuck through the West Ham defence to slot home from Harry Kane's through ball.

West Ham manager Sam Allardyce:

"We have only ourselves to blame. The game was there for us to takem but we did not and we have ended up with nothing.

"It is difficult to swallow as we dominated and played some excellent football but there were three really big factors that decided it - we did not take our chances, Mark Noble's missed penalty and allowing ourselves to go to 10 v 10.

"We created chances but this is a big league and it punishes you and it punished us today."

Tottenham manager Mauricio Pochettino:

"It was an important win. I want to say congratulations to my players because it was a great performance.

"After their penalty and our sending off it was a difficult game but we played like a team and in the end deserved to win. The sending off was a surprise because the shot was not on target. It is possible that Tottenham will appeal this.

"It was a great goal by Eric Dier. He showed, and we showed, that we are ambitious. We played like a team and that is important."

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Carlton Cole scored four goals in seven games towards the end of last season for West Ham

Kyle Naughton became the first Premier League player to be sent off this season when he handled Kevin Nolan's shot

Mauricio Pochettino was taking charge of his first competitive game as Tottenham manager since leaving Southampton

James Collins was sent off for West Ham in the second half after receiving his second yellow of the game

Born in Cheltenham, Eric Dier came through the youth system at Sporting Lisbon