Erik Lamela marked his first Premier League start of the season by firing Tottenham to a 1-0 victory at West Ham.

The Argentinian attacker was preferred to fit-again Christian Eriksen by manager Mauricio Pochettino and repaid that faith with a first-half winner.

Victory in a feisty London derby meant a fourth straight league win for Spurs to lift them into the top four.

However, back-to-back defeats for West Ham means their recent revival has hit the buffers, their promising start to the afternoon turning sour seven minutes before the interval.

Already missing six players through injury, the Hammers lost Andriy Yarmolenko to what appeared to be a serious Achilles problem which saw the winger depart on a stretcher.

If it is a recurrence of the injury he suffered at Borussia Dortmund at the start of the year Yarmolenko could be set for an extended spell on the sidelines.

Five minutes later West Ham's problems deepened, Moussa Sissoko skipping past Felipe Anderson's feeble attempt to win the ball and crossing for the unmarked Lamela to head home.

They almost went in two behind but for a double save from Lukasz Fabianski, who blocked Lamela's cross-shot and Davinson Sanchez's follow-up.

It was a miserable end to an otherwise encouraging half for the hosts, with Marko Arnautovic proving a constant nuisance to the Spurs defence after forcing an early save from Hugo Lloris.

The Hammers had also kept Harry Kane quiet until the England striker threatened to burst through on goal only for Issa Diop to make a superbly-timed last-ditch block.

Sissoko's deflected shot flew over the crossbar and Harry Winks should have done better with a volley at the far post, but there was little to trouble Manuel Pellegrini's side until Yarmolenko crumpled to the pitch inside the Spurs area.

Lloris preserved his side's lead at the start of the second half with an acrobatic save to tip over a header from Arnautovic.

Brazilian winger Anderson was enduring a torrid afternoon which was mercifully cut short before the hour mark when Pellegrini replaced him with Javier Hernandez.

Arnautovic was denied by Lloris again moments later when his shot through a crowd of bodies was tipped round the far post.

Sanchez could have doubled Tottenham's lead but planted his header over while at the other end Diop headed wide.

Five minutes before the end West Ham thought they had snatched an equaliser when Hernandez found the net but Arnautovic was offside as he played the Mexican in.

Then in stoppage time, with thick red smoke blowing across the pitch from a flare apparently let off in the crowd, Lloris came out to deny Arnautovic and secure Tottenham's derby victory.