Soccer-Southampton coast to victory at spluttering Hammers

* West Ham suffer dismal 3-0 defeat at home to Southampton * Austin opens the scoring with fifth goal in four games * Tadic makes it 2-0 before Ward-Prowse scores late third * Defeat is Hammers' second in three league games at new home * West Ham next host Middlesbrough; Southampton at Leicester (Updates with details) LONDON, Sept 25 (Reuters) - WEST HAM UNITED 0 SOUTHAMPTON 3 Southampton coasted to a 3-0 win at West Ham United in the Premier League on Sunday to record a fourth successive victory in all competitions and increase the concerns of the home fans about their team's dismal record at the new stadium. The key goals came either side of the break from Charlie Austin and Dusan Tadic while James Ward-Prowse added a third in stoppage time to complete a miserable afternoon for the Hammers. The defeat was West Ham's fourth in a row in the league - and second in succession at the London Stadium where they moved from Upton Park for the start of the season - sparking boos from disgruntled supporters at halftime and the final whistle. Austin scored with the visitors' first shot on target after 40 minutes, the striker finishing first time from a Ryan Bertrand cross for his fourth goal in five games. The 27-year-old then set up Tadic to slot home the second in the 62nd. "When you are on a hot streak you just want the goals to keep coming," said Austin, who has displaced Ireland international Shane Long in the starting lineup. "We're all fighting for places but as long as we win we're all happy." Although West Ham had a shot cleared off the line by Virgil van Dijk, they always looked vulnerable and duly conceded a 16th goal from six league games when substitute Ward-Prowse pounced. "It is not good enough," said West Ham manager Slaven Bilic. "We are a team expecting something to happen by default." (Reporting by Neil Robinson; Editing by Toby Davis and Ken Ferris)